idx
int64
func_before
string
Vulnerability Classification
string
vul
int64
func_after
string
patch
string
CWE ID
string
lines_before
string
lines_after
string
23,600
static struct oz_serial_ctx *oz_cdev_claim_ctx(struct oz_pd *pd) { struct oz_serial_ctx *ctx; spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1]; if (ctx) atomic_inc(&ctx->ref_count); spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); return ctx; }
DoS Overflow
0
static struct oz_serial_ctx *oz_cdev_claim_ctx(struct oz_pd *pd) { struct oz_serial_ctx *ctx; spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); ctx = (struct oz_serial_ctx *)pd->app_ctx[OZ_APPID_SERIAL-1]; if (ctx) atomic_inc(&ctx->ref_count); spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); return ctx; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,601
int oz_cdev_deregister(void) { cdev_del(&g_cdev.cdev); unregister_chrdev_region(g_cdev.devnum, 1); if (g_oz_class) { device_destroy(g_oz_class, g_cdev.devnum); class_destroy(g_oz_class); } return 0; }
DoS Overflow
0
int oz_cdev_deregister(void) { cdev_del(&g_cdev.cdev); unregister_chrdev_region(g_cdev.devnum, 1); if (g_oz_class) { device_destroy(g_oz_class, g_cdev.devnum); class_destroy(g_oz_class); } return 0; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,602
static long oz_cdev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { int rc = 0; if (_IOC_TYPE(cmd) != OZ_IOCTL_MAGIC) return -ENOTTY; if (_IOC_NR(cmd) > OZ_IOCTL_MAX) return -ENOTTY; if (_IOC_DIR(cmd) & _IOC_READ) rc = !access_ok(VERIFY_WRITE, (void __user *)arg, _IOC_SIZE(cmd)); else if (_IOC_DIR(cmd) & _IOC_WRITE) rc = !access_ok(VERIFY_READ, (void __user *)arg, _IOC_SIZE(cmd)); if (rc) return -EFAULT; switch (cmd) { case OZ_IOCTL_GET_PD_LIST: { struct oz_pd_list list; oz_dbg(ON, "OZ_IOCTL_GET_PD_LIST\n"); memset(&list, 0, sizeof(list)); list.count = oz_get_pd_list(list.addr, OZ_MAX_PDS); if (copy_to_user((void __user *)arg, &list, sizeof(list))) return -EFAULT; } break; case OZ_IOCTL_SET_ACTIVE_PD: { u8 addr[ETH_ALEN]; oz_dbg(ON, "OZ_IOCTL_SET_ACTIVE_PD\n"); if (copy_from_user(addr, (void __user *)arg, ETH_ALEN)) return -EFAULT; rc = oz_set_active_pd(addr); } break; case OZ_IOCTL_GET_ACTIVE_PD: { u8 addr[ETH_ALEN]; oz_dbg(ON, "OZ_IOCTL_GET_ACTIVE_PD\n"); spin_lock_bh(&g_cdev.lock); memcpy(addr, g_cdev.active_addr, ETH_ALEN); spin_unlock_bh(&g_cdev.lock); if (copy_to_user((void __user *)arg, addr, ETH_ALEN)) return -EFAULT; } break; case OZ_IOCTL_ADD_BINDING: case OZ_IOCTL_REMOVE_BINDING: { struct oz_binding_info b; if (copy_from_user(&b, (void __user *)arg, sizeof(struct oz_binding_info))) { return -EFAULT; } /* Make sure name is null terminated. */ b.name[OZ_MAX_BINDING_LEN-1] = 0; if (cmd == OZ_IOCTL_ADD_BINDING) oz_binding_add(b.name); else oz_binding_remove(b.name); } break; } return rc; }
DoS Overflow
0
static long oz_cdev_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { int rc = 0; if (_IOC_TYPE(cmd) != OZ_IOCTL_MAGIC) return -ENOTTY; if (_IOC_NR(cmd) > OZ_IOCTL_MAX) return -ENOTTY; if (_IOC_DIR(cmd) & _IOC_READ) rc = !access_ok(VERIFY_WRITE, (void __user *)arg, _IOC_SIZE(cmd)); else if (_IOC_DIR(cmd) & _IOC_WRITE) rc = !access_ok(VERIFY_READ, (void __user *)arg, _IOC_SIZE(cmd)); if (rc) return -EFAULT; switch (cmd) { case OZ_IOCTL_GET_PD_LIST: { struct oz_pd_list list; oz_dbg(ON, "OZ_IOCTL_GET_PD_LIST\n"); memset(&list, 0, sizeof(list)); list.count = oz_get_pd_list(list.addr, OZ_MAX_PDS); if (copy_to_user((void __user *)arg, &list, sizeof(list))) return -EFAULT; } break; case OZ_IOCTL_SET_ACTIVE_PD: { u8 addr[ETH_ALEN]; oz_dbg(ON, "OZ_IOCTL_SET_ACTIVE_PD\n"); if (copy_from_user(addr, (void __user *)arg, ETH_ALEN)) return -EFAULT; rc = oz_set_active_pd(addr); } break; case OZ_IOCTL_GET_ACTIVE_PD: { u8 addr[ETH_ALEN]; oz_dbg(ON, "OZ_IOCTL_GET_ACTIVE_PD\n"); spin_lock_bh(&g_cdev.lock); memcpy(addr, g_cdev.active_addr, ETH_ALEN); spin_unlock_bh(&g_cdev.lock); if (copy_to_user((void __user *)arg, addr, ETH_ALEN)) return -EFAULT; } break; case OZ_IOCTL_ADD_BINDING: case OZ_IOCTL_REMOVE_BINDING: { struct oz_binding_info b; if (copy_from_user(&b, (void __user *)arg, sizeof(struct oz_binding_info))) { return -EFAULT; } /* Make sure name is null terminated. */ b.name[OZ_MAX_BINDING_LEN-1] = 0; if (cmd == OZ_IOCTL_ADD_BINDING) oz_binding_add(b.name); else oz_binding_remove(b.name); } break; } return rc; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,603
static int oz_cdev_open(struct inode *inode, struct file *filp) { struct oz_cdev *dev = container_of(inode->i_cdev, struct oz_cdev, cdev); oz_dbg(ON, "major = %d minor = %d\n", imajor(inode), iminor(inode)); filp->private_data = dev; return 0; }
DoS Overflow
0
static int oz_cdev_open(struct inode *inode, struct file *filp) { struct oz_cdev *dev = container_of(inode->i_cdev, struct oz_cdev, cdev); oz_dbg(ON, "major = %d minor = %d\n", imajor(inode), iminor(inode)); filp->private_data = dev; return 0; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,604
static unsigned int oz_cdev_poll(struct file *filp, poll_table *wait) { unsigned int ret = 0; struct oz_cdev *dev = filp->private_data; oz_dbg(ON, "Poll called wait = %p\n", wait); spin_lock_bh(&dev->lock); if (dev->active_pd) { struct oz_serial_ctx *ctx = oz_cdev_claim_ctx(dev->active_pd); if (ctx) { if (ctx->rd_in != ctx->rd_out) ret |= POLLIN | POLLRDNORM; oz_cdev_release_ctx(ctx); } } spin_unlock_bh(&dev->lock); if (wait) poll_wait(filp, &dev->rdq, wait); return ret; }
DoS Overflow
0
static unsigned int oz_cdev_poll(struct file *filp, poll_table *wait) { unsigned int ret = 0; struct oz_cdev *dev = filp->private_data; oz_dbg(ON, "Poll called wait = %p\n", wait); spin_lock_bh(&dev->lock); if (dev->active_pd) { struct oz_serial_ctx *ctx = oz_cdev_claim_ctx(dev->active_pd); if (ctx) { if (ctx->rd_in != ctx->rd_out) ret |= POLLIN | POLLRDNORM; oz_cdev_release_ctx(ctx); } } spin_unlock_bh(&dev->lock); if (wait) poll_wait(filp, &dev->rdq, wait); return ret; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,605
static ssize_t oz_cdev_read(struct file *filp, char __user *buf, size_t count, loff_t *fpos) { int n; int ix; struct oz_pd *pd; struct oz_serial_ctx *ctx; spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd) oz_pd_get(pd); spin_unlock_bh(&g_cdev.lock); if (pd == NULL) return -1; ctx = oz_cdev_claim_ctx(pd); if (ctx == NULL) goto out2; n = ctx->rd_in - ctx->rd_out; if (n < 0) n += OZ_RD_BUF_SZ; if (count > n) count = n; ix = ctx->rd_out; n = OZ_RD_BUF_SZ - ix; if (n > count) n = count; if (copy_to_user(buf, &ctx->rd_buf[ix], n)) { count = 0; goto out1; } ix += n; if (ix == OZ_RD_BUF_SZ) ix = 0; if (n < count) { if (copy_to_user(&buf[n], ctx->rd_buf, count-n)) { count = 0; goto out1; } ix = count-n; } ctx->rd_out = ix; out1: oz_cdev_release_ctx(ctx); out2: oz_pd_put(pd); return count; }
DoS Overflow
0
static ssize_t oz_cdev_read(struct file *filp, char __user *buf, size_t count, loff_t *fpos) { int n; int ix; struct oz_pd *pd; struct oz_serial_ctx *ctx; spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd) oz_pd_get(pd); spin_unlock_bh(&g_cdev.lock); if (pd == NULL) return -1; ctx = oz_cdev_claim_ctx(pd); if (ctx == NULL) goto out2; n = ctx->rd_in - ctx->rd_out; if (n < 0) n += OZ_RD_BUF_SZ; if (count > n) count = n; ix = ctx->rd_out; n = OZ_RD_BUF_SZ - ix; if (n > count) n = count; if (copy_to_user(buf, &ctx->rd_buf[ix], n)) { count = 0; goto out1; } ix += n; if (ix == OZ_RD_BUF_SZ) ix = 0; if (n < count) { if (copy_to_user(&buf[n], ctx->rd_buf, count-n)) { count = 0; goto out1; } ix = count-n; } ctx->rd_out = ix; out1: oz_cdev_release_ctx(ctx); out2: oz_pd_put(pd); return count; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,606
int oz_cdev_register(void) { int err; struct device *dev; memset(&g_cdev, 0, sizeof(g_cdev)); err = alloc_chrdev_region(&g_cdev.devnum, 0, 1, "ozwpan"); if (err < 0) return err; oz_dbg(ON, "Alloc dev number %d:%d\n", MAJOR(g_cdev.devnum), MINOR(g_cdev.devnum)); cdev_init(&g_cdev.cdev, &oz_fops); g_cdev.cdev.owner = THIS_MODULE; g_cdev.cdev.ops = &oz_fops; spin_lock_init(&g_cdev.lock); init_waitqueue_head(&g_cdev.rdq); err = cdev_add(&g_cdev.cdev, g_cdev.devnum, 1); if (err < 0) { oz_dbg(ON, "Failed to add cdev\n"); goto unregister; } g_oz_class = class_create(THIS_MODULE, "ozmo_wpan"); if (IS_ERR(g_oz_class)) { oz_dbg(ON, "Failed to register ozmo_wpan class\n"); err = PTR_ERR(g_oz_class); goto delete; } dev = device_create(g_oz_class, NULL, g_cdev.devnum, NULL, "ozwpan"); if (IS_ERR(dev)) { oz_dbg(ON, "Failed to create sysfs entry for cdev\n"); err = PTR_ERR(dev); goto delete; } return 0; delete: cdev_del(&g_cdev.cdev); unregister: unregister_chrdev_region(g_cdev.devnum, 1); return err; }
DoS Overflow
0
int oz_cdev_register(void) { int err; struct device *dev; memset(&g_cdev, 0, sizeof(g_cdev)); err = alloc_chrdev_region(&g_cdev.devnum, 0, 1, "ozwpan"); if (err < 0) return err; oz_dbg(ON, "Alloc dev number %d:%d\n", MAJOR(g_cdev.devnum), MINOR(g_cdev.devnum)); cdev_init(&g_cdev.cdev, &oz_fops); g_cdev.cdev.owner = THIS_MODULE; g_cdev.cdev.ops = &oz_fops; spin_lock_init(&g_cdev.lock); init_waitqueue_head(&g_cdev.rdq); err = cdev_add(&g_cdev.cdev, g_cdev.devnum, 1); if (err < 0) { oz_dbg(ON, "Failed to add cdev\n"); goto unregister; } g_oz_class = class_create(THIS_MODULE, "ozmo_wpan"); if (IS_ERR(g_oz_class)) { oz_dbg(ON, "Failed to register ozmo_wpan class\n"); err = PTR_ERR(g_oz_class); goto delete; } dev = device_create(g_oz_class, NULL, g_cdev.devnum, NULL, "ozwpan"); if (IS_ERR(dev)) { oz_dbg(ON, "Failed to create sysfs entry for cdev\n"); err = PTR_ERR(dev); goto delete; } return 0; delete: cdev_del(&g_cdev.cdev); unregister: unregister_chrdev_region(g_cdev.devnum, 1); return err; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,607
static int oz_cdev_release(struct inode *inode, struct file *filp) { return 0; }
DoS Overflow
0
static int oz_cdev_release(struct inode *inode, struct file *filp) { return 0; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,608
static void oz_cdev_release_ctx(struct oz_serial_ctx *ctx) { if (atomic_dec_and_test(&ctx->ref_count)) { oz_dbg(ON, "Dealloc serial context\n"); kfree(ctx); } }
DoS Overflow
0
static void oz_cdev_release_ctx(struct oz_serial_ctx *ctx) { if (atomic_dec_and_test(&ctx->ref_count)) { oz_dbg(ON, "Dealloc serial context\n"); kfree(ctx); } }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,609
int oz_cdev_start(struct oz_pd *pd, int resume) { struct oz_serial_ctx *ctx; struct oz_serial_ctx *old_ctx; if (resume) { oz_dbg(ON, "Serial service resumed\n"); return 0; } ctx = kzalloc(sizeof(struct oz_serial_ctx), GFP_ATOMIC); if (ctx == NULL) return -ENOMEM; atomic_set(&ctx->ref_count, 1); ctx->tx_seq_num = 1; spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); old_ctx = pd->app_ctx[OZ_APPID_SERIAL-1]; if (old_ctx) { spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); kfree(ctx); } else { pd->app_ctx[OZ_APPID_SERIAL-1] = ctx; spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); } spin_lock(&g_cdev.lock); if ((g_cdev.active_pd == NULL) && (memcmp(pd->mac_addr, g_cdev.active_addr, ETH_ALEN) == 0)) { oz_pd_get(pd); g_cdev.active_pd = pd; oz_dbg(ON, "Active PD arrived\n"); } spin_unlock(&g_cdev.lock); oz_dbg(ON, "Serial service started\n"); return 0; }
DoS Overflow
0
int oz_cdev_start(struct oz_pd *pd, int resume) { struct oz_serial_ctx *ctx; struct oz_serial_ctx *old_ctx; if (resume) { oz_dbg(ON, "Serial service resumed\n"); return 0; } ctx = kzalloc(sizeof(struct oz_serial_ctx), GFP_ATOMIC); if (ctx == NULL) return -ENOMEM; atomic_set(&ctx->ref_count, 1); ctx->tx_seq_num = 1; spin_lock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); old_ctx = pd->app_ctx[OZ_APPID_SERIAL-1]; if (old_ctx) { spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); kfree(ctx); } else { pd->app_ctx[OZ_APPID_SERIAL-1] = ctx; spin_unlock_bh(&pd->app_lock[OZ_APPID_SERIAL-1]); } spin_lock(&g_cdev.lock); if ((g_cdev.active_pd == NULL) && (memcmp(pd->mac_addr, g_cdev.active_addr, ETH_ALEN) == 0)) { oz_pd_get(pd); g_cdev.active_pd = pd; oz_dbg(ON, "Active PD arrived\n"); } spin_unlock(&g_cdev.lock); oz_dbg(ON, "Serial service started\n"); return 0; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,610
void oz_cdev_term(void) { oz_app_enable(OZ_APPID_SERIAL, 0); }
DoS Overflow
0
void oz_cdev_term(void) { oz_app_enable(OZ_APPID_SERIAL, 0); }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,611
static int oz_set_active_pd(const u8 *addr) { int rc = 0; struct oz_pd *pd; struct oz_pd *old_pd; pd = oz_pd_find(addr); if (pd) { spin_lock_bh(&g_cdev.lock); memcpy(g_cdev.active_addr, addr, ETH_ALEN); old_pd = g_cdev.active_pd; g_cdev.active_pd = pd; spin_unlock_bh(&g_cdev.lock); if (old_pd) oz_pd_put(old_pd); } else { if (is_zero_ether_addr(addr)) { spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; g_cdev.active_pd = NULL; memset(g_cdev.active_addr, 0, sizeof(g_cdev.active_addr)); spin_unlock_bh(&g_cdev.lock); if (pd) oz_pd_put(pd); } else { rc = -1; } } return rc; }
DoS Overflow
0
static int oz_set_active_pd(const u8 *addr) { int rc = 0; struct oz_pd *pd; struct oz_pd *old_pd; pd = oz_pd_find(addr); if (pd) { spin_lock_bh(&g_cdev.lock); memcpy(g_cdev.active_addr, addr, ETH_ALEN); old_pd = g_cdev.active_pd; g_cdev.active_pd = pd; spin_unlock_bh(&g_cdev.lock); if (old_pd) oz_pd_put(old_pd); } else { if (is_zero_ether_addr(addr)) { spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; g_cdev.active_pd = NULL; memset(g_cdev.active_addr, 0, sizeof(g_cdev.active_addr)); spin_unlock_bh(&g_cdev.lock); if (pd) oz_pd_put(pd); } else { rc = -1; } } return rc; }
@@ -155,6 +155,9 @@ static ssize_t oz_cdev_write(struct file *filp, const char __user *buf, struct oz_app_hdr *app_hdr; struct oz_serial_ctx *ctx; + if (count > sizeof(ei->data) - sizeof(*elt) - sizeof(*app_hdr)) + return -EINVAL; + spin_lock_bh(&g_cdev.lock); pd = g_cdev.active_pd; if (pd)
CWE-119
null
null
23,612
static int exitcode_proc_open(struct inode *inode, struct file *file) { return single_open(file, exitcode_proc_show, NULL); }
DoS Overflow
0
static int exitcode_proc_open(struct inode *inode, struct file *file) { return single_open(file, exitcode_proc_show, NULL); }
@@ -40,9 +40,11 @@ static ssize_t exitcode_proc_write(struct file *file, const char __user *buffer, size_t count, loff_t *pos) { char *end, buf[sizeof("nnnnn\0")]; + size_t size; int tmp; - if (copy_from_user(buf, buffer, count)) + size = min(count, sizeof(buf)); + if (copy_from_user(buf, buffer, size)) return -EFAULT; tmp = simple_strtol(buf, &end, 0);
CWE-119
null
null
23,613
static int make_proc_exitcode(void) { struct proc_dir_entry *ent; ent = proc_create("exitcode", 0600, NULL, &exitcode_proc_fops); if (ent == NULL) { printk(KERN_WARNING "make_proc_exitcode : Failed to register " "/proc/exitcode\n"); return 0; } return 0; }
DoS Overflow
0
static int make_proc_exitcode(void) { struct proc_dir_entry *ent; ent = proc_create("exitcode", 0600, NULL, &exitcode_proc_fops); if (ent == NULL) { printk(KERN_WARNING "make_proc_exitcode : Failed to register " "/proc/exitcode\n"); return 0; } return 0; }
@@ -40,9 +40,11 @@ static ssize_t exitcode_proc_write(struct file *file, const char __user *buffer, size_t count, loff_t *pos) { char *end, buf[sizeof("nnnnn\0")]; + size_t size; int tmp; - if (copy_from_user(buf, buffer, count)) + size = min(count, sizeof(buf)); + if (copy_from_user(buf, buffer, size)) return -EFAULT; tmp = simple_strtol(buf, &end, 0);
CWE-119
null
null
23,614
SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg) { struct ipc_namespace *ns; struct ipc_ops msg_ops; struct ipc_params msg_params; ns = current->nsproxy->ipc_ns; msg_ops.getnew = newque; msg_ops.associate = msg_security; msg_ops.more_checks = NULL; msg_params.key = key; msg_params.flg = msgflg; return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params); }
DoS
0
SYSCALL_DEFINE2(msgget, key_t, key, int, msgflg) { struct ipc_namespace *ns; struct ipc_ops msg_ops; struct ipc_params msg_params; ns = current->nsproxy->ipc_ns; msg_ops.getnew = newque; msg_ops.associate = msg_security; msg_ops.more_checks = NULL; msg_params.key = key; msg_params.flg = msgflg; return ipcget(ns, &msg_ids(ns), &msg_ops, &msg_params); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,615
SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf) { struct msg_queue *msq; int err, version; struct ipc_namespace *ns; if (msqid < 0 || cmd < 0) return -EINVAL; version = ipc_parse_version(&cmd); ns = current->nsproxy->ipc_ns; switch (cmd) { case IPC_INFO: case MSG_INFO: { struct msginfo msginfo; int max_id; if (!buf) return -EFAULT; /* * We must not return kernel stack data. * due to padding, it's not enough * to set all member fields. */ err = security_msg_queue_msgctl(NULL, cmd); if (err) return err; memset(&msginfo, 0, sizeof(msginfo)); msginfo.msgmni = ns->msg_ctlmni; msginfo.msgmax = ns->msg_ctlmax; msginfo.msgmnb = ns->msg_ctlmnb; msginfo.msgssz = MSGSSZ; msginfo.msgseg = MSGSEG; down_read(&msg_ids(ns).rw_mutex); if (cmd == MSG_INFO) { msginfo.msgpool = msg_ids(ns).in_use; msginfo.msgmap = atomic_read(&ns->msg_hdrs); msginfo.msgtql = atomic_read(&ns->msg_bytes); } else { msginfo.msgmap = MSGMAP; msginfo.msgpool = MSGPOOL; msginfo.msgtql = MSGTQL; } max_id = ipc_get_maxid(&msg_ids(ns)); up_read(&msg_ids(ns).rw_mutex); if (copy_to_user(buf, &msginfo, sizeof(struct msginfo))) return -EFAULT; return (max_id < 0) ? 0 : max_id; } case MSG_STAT: /* msqid is an index rather than a msg queue id */ case IPC_STAT: { struct msqid64_ds tbuf; int success_return; if (!buf) return -EFAULT; if (cmd == MSG_STAT) { msq = msg_lock(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = msq->q_perm.id; } else { msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = 0; } err = -EACCES; if (ipcperms(ns, &msq->q_perm, S_IRUGO)) goto out_unlock; err = security_msg_queue_msgctl(msq, cmd); if (err) goto out_unlock; memset(&tbuf, 0, sizeof(tbuf)); kernel_to_ipc64_perm(&msq->q_perm, &tbuf.msg_perm); tbuf.msg_stime = msq->q_stime; tbuf.msg_rtime = msq->q_rtime; tbuf.msg_ctime = msq->q_ctime; tbuf.msg_cbytes = msq->q_cbytes; tbuf.msg_qnum = msq->q_qnum; tbuf.msg_qbytes = msq->q_qbytes; tbuf.msg_lspid = msq->q_lspid; tbuf.msg_lrpid = msq->q_lrpid; msg_unlock(msq); if (copy_msqid_to_user(buf, &tbuf, version)) return -EFAULT; return success_return; } case IPC_SET: case IPC_RMID: err = msgctl_down(ns, msqid, cmd, buf, version); return err; default: return -EINVAL; } out_unlock: msg_unlock(msq); return err; }
DoS
0
SYSCALL_DEFINE3(msgctl, int, msqid, int, cmd, struct msqid_ds __user *, buf) { struct msg_queue *msq; int err, version; struct ipc_namespace *ns; if (msqid < 0 || cmd < 0) return -EINVAL; version = ipc_parse_version(&cmd); ns = current->nsproxy->ipc_ns; switch (cmd) { case IPC_INFO: case MSG_INFO: { struct msginfo msginfo; int max_id; if (!buf) return -EFAULT; /* * We must not return kernel stack data. * due to padding, it's not enough * to set all member fields. */ err = security_msg_queue_msgctl(NULL, cmd); if (err) return err; memset(&msginfo, 0, sizeof(msginfo)); msginfo.msgmni = ns->msg_ctlmni; msginfo.msgmax = ns->msg_ctlmax; msginfo.msgmnb = ns->msg_ctlmnb; msginfo.msgssz = MSGSSZ; msginfo.msgseg = MSGSEG; down_read(&msg_ids(ns).rw_mutex); if (cmd == MSG_INFO) { msginfo.msgpool = msg_ids(ns).in_use; msginfo.msgmap = atomic_read(&ns->msg_hdrs); msginfo.msgtql = atomic_read(&ns->msg_bytes); } else { msginfo.msgmap = MSGMAP; msginfo.msgpool = MSGPOOL; msginfo.msgtql = MSGTQL; } max_id = ipc_get_maxid(&msg_ids(ns)); up_read(&msg_ids(ns).rw_mutex); if (copy_to_user(buf, &msginfo, sizeof(struct msginfo))) return -EFAULT; return (max_id < 0) ? 0 : max_id; } case MSG_STAT: /* msqid is an index rather than a msg queue id */ case IPC_STAT: { struct msqid64_ds tbuf; int success_return; if (!buf) return -EFAULT; if (cmd == MSG_STAT) { msq = msg_lock(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = msq->q_perm.id; } else { msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) return PTR_ERR(msq); success_return = 0; } err = -EACCES; if (ipcperms(ns, &msq->q_perm, S_IRUGO)) goto out_unlock; err = security_msg_queue_msgctl(msq, cmd); if (err) goto out_unlock; memset(&tbuf, 0, sizeof(tbuf)); kernel_to_ipc64_perm(&msq->q_perm, &tbuf.msg_perm); tbuf.msg_stime = msq->q_stime; tbuf.msg_rtime = msq->q_rtime; tbuf.msg_ctime = msq->q_ctime; tbuf.msg_cbytes = msq->q_cbytes; tbuf.msg_qnum = msq->q_qnum; tbuf.msg_qbytes = msq->q_qbytes; tbuf.msg_lspid = msq->q_lspid; tbuf.msg_lrpid = msq->q_lrpid; msg_unlock(msq); if (copy_msqid_to_user(buf, &tbuf, version)) return -EFAULT; return success_return; } case IPC_SET: case IPC_RMID: err = msgctl_down(ns, msqid, cmd, buf, version); return err; default: return -EINVAL; } out_unlock: msg_unlock(msq); return err; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,616
SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, long, msgtyp, int, msgflg) { return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill); }
DoS
0
SYSCALL_DEFINE5(msgrcv, int, msqid, struct msgbuf __user *, msgp, size_t, msgsz, long, msgtyp, int, msgflg) { return do_msgrcv(msqid, msgp, msgsz, msgtyp, msgflg, do_msg_fill); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,617
static inline int convert_mode(long *msgtyp, int msgflg) { if (msgflg & MSG_COPY) return SEARCH_NUMBER; /* * find message of correct type. * msgtyp = 0 => get first. * msgtyp > 0 => get first message of matching type. * msgtyp < 0 => get message with least type must be < abs(msgtype). */ if (*msgtyp == 0) return SEARCH_ANY; if (*msgtyp < 0) { *msgtyp = -*msgtyp; return SEARCH_LESSEQUAL; } if (msgflg & MSG_EXCEPT) return SEARCH_NOTEQUAL; return SEARCH_EQUAL; }
DoS
0
static inline int convert_mode(long *msgtyp, int msgflg) { if (msgflg & MSG_COPY) return SEARCH_NUMBER; /* * find message of correct type. * msgtyp = 0 => get first. * msgtyp > 0 => get first message of matching type. * msgtyp < 0 => get message with least type must be < abs(msgtype). */ if (*msgtyp == 0) return SEARCH_ANY; if (*msgtyp < 0) { *msgtyp = -*msgtyp; return SEARCH_LESSEQUAL; } if (msgflg & MSG_EXCEPT) return SEARCH_NOTEQUAL; return SEARCH_EQUAL; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,618
copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version) { switch(version) { case IPC_64: if (copy_from_user(out, buf, sizeof(*out))) return -EFAULT; return 0; case IPC_OLD: { struct msqid_ds tbuf_old; if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) return -EFAULT; out->msg_perm.uid = tbuf_old.msg_perm.uid; out->msg_perm.gid = tbuf_old.msg_perm.gid; out->msg_perm.mode = tbuf_old.msg_perm.mode; if (tbuf_old.msg_qbytes == 0) out->msg_qbytes = tbuf_old.msg_lqbytes; else out->msg_qbytes = tbuf_old.msg_qbytes; return 0; } default: return -EINVAL; } }
DoS
0
copy_msqid_from_user(struct msqid64_ds *out, void __user *buf, int version) { switch(version) { case IPC_64: if (copy_from_user(out, buf, sizeof(*out))) return -EFAULT; return 0; case IPC_OLD: { struct msqid_ds tbuf_old; if (copy_from_user(&tbuf_old, buf, sizeof(tbuf_old))) return -EFAULT; out->msg_perm.uid = tbuf_old.msg_perm.uid; out->msg_perm.gid = tbuf_old.msg_perm.gid; out->msg_perm.mode = tbuf_old.msg_perm.mode; if (tbuf_old.msg_qbytes == 0) out->msg_qbytes = tbuf_old.msg_lqbytes; else out->msg_qbytes = tbuf_old.msg_qbytes; return 0; } default: return -EINVAL; } }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,619
copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version) { switch(version) { case IPC_64: return copy_to_user(buf, in, sizeof(*in)); case IPC_OLD: { struct msqid_ds out; memset(&out, 0, sizeof(out)); ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm); out.msg_stime = in->msg_stime; out.msg_rtime = in->msg_rtime; out.msg_ctime = in->msg_ctime; if (in->msg_cbytes > USHRT_MAX) out.msg_cbytes = USHRT_MAX; else out.msg_cbytes = in->msg_cbytes; out.msg_lcbytes = in->msg_cbytes; if (in->msg_qnum > USHRT_MAX) out.msg_qnum = USHRT_MAX; else out.msg_qnum = in->msg_qnum; if (in->msg_qbytes > USHRT_MAX) out.msg_qbytes = USHRT_MAX; else out.msg_qbytes = in->msg_qbytes; out.msg_lqbytes = in->msg_qbytes; out.msg_lspid = in->msg_lspid; out.msg_lrpid = in->msg_lrpid; return copy_to_user(buf, &out, sizeof(out)); } default: return -EINVAL; } }
DoS
0
copy_msqid_to_user(void __user *buf, struct msqid64_ds *in, int version) { switch(version) { case IPC_64: return copy_to_user(buf, in, sizeof(*in)); case IPC_OLD: { struct msqid_ds out; memset(&out, 0, sizeof(out)); ipc64_perm_to_ipc_perm(&in->msg_perm, &out.msg_perm); out.msg_stime = in->msg_stime; out.msg_rtime = in->msg_rtime; out.msg_ctime = in->msg_ctime; if (in->msg_cbytes > USHRT_MAX) out.msg_cbytes = USHRT_MAX; else out.msg_cbytes = in->msg_cbytes; out.msg_lcbytes = in->msg_cbytes; if (in->msg_qnum > USHRT_MAX) out.msg_qnum = USHRT_MAX; else out.msg_qnum = in->msg_qnum; if (in->msg_qbytes > USHRT_MAX) out.msg_qbytes = USHRT_MAX; else out.msg_qbytes = in->msg_qbytes; out.msg_lqbytes = in->msg_qbytes; out.msg_lspid = in->msg_lspid; out.msg_lrpid = in->msg_lrpid; return copy_to_user(buf, &out, sizeof(out)); } default: return -EINVAL; } }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,620
static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz) { struct msgbuf __user *msgp = dest; size_t msgsz; if (put_user(msg->m_type, &msgp->mtype)) return -EFAULT; msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz; if (store_msg(msgp->mtext, msg, msgsz)) return -EFAULT; return msgsz; }
DoS
0
static long do_msg_fill(void __user *dest, struct msg_msg *msg, size_t bufsz) { struct msgbuf __user *msgp = dest; size_t msgsz; if (put_user(msg->m_type, &msgp->mtype)) return -EFAULT; msgsz = (bufsz > msg->m_ts) ? msg->m_ts : bufsz; if (store_msg(msgp->mtext, msg, msgsz)) return -EFAULT; return msgsz; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,621
long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgflg, long (*msg_handler)(void __user *, struct msg_msg *, size_t)) { struct msg_queue *msq; struct msg_msg *msg; int mode; struct ipc_namespace *ns; struct msg_msg *copy = NULL; ns = current->nsproxy->ipc_ns; if (msqid < 0 || (long) bufsz < 0) return -EINVAL; if (msgflg & MSG_COPY) { copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax)); if (IS_ERR(copy)) return PTR_ERR(copy); } mode = convert_mode(&msgtyp, msgflg); msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) { free_copy(copy); return PTR_ERR(msq); } for (;;) { struct msg_receiver msr_d; msg = ERR_PTR(-EACCES); if (ipcperms(ns, &msq->q_perm, S_IRUGO)) goto out_unlock; msg = find_msg(msq, &msgtyp, mode); if (!IS_ERR(msg)) { /* * Found a suitable message. * Unlink it from the queue. */ if ((bufsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) { msg = ERR_PTR(-E2BIG); goto out_unlock; } /* * If we are copying, then do not unlink message and do * not update queue parameters. */ if (msgflg & MSG_COPY) { msg = copy_msg(msg, copy); goto out_unlock; } list_del(&msg->m_list); msq->q_qnum--; msq->q_rtime = get_seconds(); msq->q_lrpid = task_tgid_vnr(current); msq->q_cbytes -= msg->m_ts; atomic_sub(msg->m_ts, &ns->msg_bytes); atomic_dec(&ns->msg_hdrs); ss_wakeup(&msq->q_senders, 0); msg_unlock(msq); break; } /* No message waiting. Wait for a message */ if (msgflg & IPC_NOWAIT) { msg = ERR_PTR(-ENOMSG); goto out_unlock; } list_add_tail(&msr_d.r_list, &msq->q_receivers); msr_d.r_tsk = current; msr_d.r_msgtype = msgtyp; msr_d.r_mode = mode; if (msgflg & MSG_NOERROR) msr_d.r_maxsize = INT_MAX; else msr_d.r_maxsize = bufsz; msr_d.r_msg = ERR_PTR(-EAGAIN); current->state = TASK_INTERRUPTIBLE; msg_unlock(msq); schedule(); /* Lockless receive, part 1: * Disable preemption. We don't hold a reference to the queue * and getting a reference would defeat the idea of a lockless * operation, thus the code relies on rcu to guarantee the * existence of msq: * Prior to destruction, expunge_all(-EIRDM) changes r_msg. * Thus if r_msg is -EAGAIN, then the queue not yet destroyed. * rcu_read_lock() prevents preemption between reading r_msg * and the spin_lock() inside ipc_lock_by_ptr(). */ rcu_read_lock(); /* Lockless receive, part 2: * Wait until pipelined_send or expunge_all are outside of * wake_up_process(). There is a race with exit(), see * ipc/mqueue.c for the details. */ msg = (struct msg_msg*)msr_d.r_msg; while (msg == NULL) { cpu_relax(); msg = (struct msg_msg *)msr_d.r_msg; } /* Lockless receive, part 3: * If there is a message or an error then accept it without * locking. */ if (msg != ERR_PTR(-EAGAIN)) { rcu_read_unlock(); break; } /* Lockless receive, part 3: * Acquire the queue spinlock. */ ipc_lock_by_ptr(&msq->q_perm); rcu_read_unlock(); /* Lockless receive, part 4: * Repeat test after acquiring the spinlock. */ msg = (struct msg_msg*)msr_d.r_msg; if (msg != ERR_PTR(-EAGAIN)) goto out_unlock; list_del(&msr_d.r_list); if (signal_pending(current)) { msg = ERR_PTR(-ERESTARTNOHAND); out_unlock: msg_unlock(msq); break; } } if (IS_ERR(msg)) { free_copy(copy); return PTR_ERR(msg); } bufsz = msg_handler(buf, msg, bufsz); free_msg(msg); return bufsz; }
DoS
0
long do_msgrcv(int msqid, void __user *buf, size_t bufsz, long msgtyp, int msgflg, long (*msg_handler)(void __user *, struct msg_msg *, size_t)) { struct msg_queue *msq; struct msg_msg *msg; int mode; struct ipc_namespace *ns; struct msg_msg *copy = NULL; ns = current->nsproxy->ipc_ns; if (msqid < 0 || (long) bufsz < 0) return -EINVAL; if (msgflg & MSG_COPY) { copy = prepare_copy(buf, min_t(size_t, bufsz, ns->msg_ctlmax)); if (IS_ERR(copy)) return PTR_ERR(copy); } mode = convert_mode(&msgtyp, msgflg); msq = msg_lock_check(ns, msqid); if (IS_ERR(msq)) { free_copy(copy); return PTR_ERR(msq); } for (;;) { struct msg_receiver msr_d; msg = ERR_PTR(-EACCES); if (ipcperms(ns, &msq->q_perm, S_IRUGO)) goto out_unlock; msg = find_msg(msq, &msgtyp, mode); if (!IS_ERR(msg)) { /* * Found a suitable message. * Unlink it from the queue. */ if ((bufsz < msg->m_ts) && !(msgflg & MSG_NOERROR)) { msg = ERR_PTR(-E2BIG); goto out_unlock; } /* * If we are copying, then do not unlink message and do * not update queue parameters. */ if (msgflg & MSG_COPY) { msg = copy_msg(msg, copy); goto out_unlock; } list_del(&msg->m_list); msq->q_qnum--; msq->q_rtime = get_seconds(); msq->q_lrpid = task_tgid_vnr(current); msq->q_cbytes -= msg->m_ts; atomic_sub(msg->m_ts, &ns->msg_bytes); atomic_dec(&ns->msg_hdrs); ss_wakeup(&msq->q_senders, 0); msg_unlock(msq); break; } /* No message waiting. Wait for a message */ if (msgflg & IPC_NOWAIT) { msg = ERR_PTR(-ENOMSG); goto out_unlock; } list_add_tail(&msr_d.r_list, &msq->q_receivers); msr_d.r_tsk = current; msr_d.r_msgtype = msgtyp; msr_d.r_mode = mode; if (msgflg & MSG_NOERROR) msr_d.r_maxsize = INT_MAX; else msr_d.r_maxsize = bufsz; msr_d.r_msg = ERR_PTR(-EAGAIN); current->state = TASK_INTERRUPTIBLE; msg_unlock(msq); schedule(); /* Lockless receive, part 1: * Disable preemption. We don't hold a reference to the queue * and getting a reference would defeat the idea of a lockless * operation, thus the code relies on rcu to guarantee the * existence of msq: * Prior to destruction, expunge_all(-EIRDM) changes r_msg. * Thus if r_msg is -EAGAIN, then the queue not yet destroyed. * rcu_read_lock() prevents preemption between reading r_msg * and the spin_lock() inside ipc_lock_by_ptr(). */ rcu_read_lock(); /* Lockless receive, part 2: * Wait until pipelined_send or expunge_all are outside of * wake_up_process(). There is a race with exit(), see * ipc/mqueue.c for the details. */ msg = (struct msg_msg*)msr_d.r_msg; while (msg == NULL) { cpu_relax(); msg = (struct msg_msg *)msr_d.r_msg; } /* Lockless receive, part 3: * If there is a message or an error then accept it without * locking. */ if (msg != ERR_PTR(-EAGAIN)) { rcu_read_unlock(); break; } /* Lockless receive, part 3: * Acquire the queue spinlock. */ ipc_lock_by_ptr(&msq->q_perm); rcu_read_unlock(); /* Lockless receive, part 4: * Repeat test after acquiring the spinlock. */ msg = (struct msg_msg*)msr_d.r_msg; if (msg != ERR_PTR(-EAGAIN)) goto out_unlock; list_del(&msr_d.r_list); if (signal_pending(current)) { msg = ERR_PTR(-ERESTARTNOHAND); out_unlock: msg_unlock(msq); break; } } if (IS_ERR(msg)) { free_copy(copy); return PTR_ERR(msg); } bufsz = msg_handler(buf, msg, bufsz); free_msg(msg); return bufsz; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,622
static void expunge_all(struct msg_queue *msq, int res) { struct list_head *tmp; tmp = msq->q_receivers.next; while (tmp != &msq->q_receivers) { struct msg_receiver *msr; msr = list_entry(tmp, struct msg_receiver, r_list); tmp = tmp->next; msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(res); } }
DoS
0
static void expunge_all(struct msg_queue *msq, int res) { struct list_head *tmp; tmp = msq->q_receivers.next; while (tmp != &msq->q_receivers) { struct msg_receiver *msr; msr = list_entry(tmp, struct msg_receiver, r_list); tmp = tmp->next; msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(res); } }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,623
static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode) { struct msg_msg *msg; long count = 0; list_for_each_entry(msg, &msq->q_messages, m_list) { if (testmsg(msg, *msgtyp, mode) && !security_msg_queue_msgrcv(msq, msg, current, *msgtyp, mode)) { if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) { *msgtyp = msg->m_type - 1; } else if (mode == SEARCH_NUMBER) { if (*msgtyp == count) return msg; } else return msg; count++; } } return ERR_PTR(-EAGAIN); }
DoS
0
static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode) { struct msg_msg *msg; long count = 0; list_for_each_entry(msg, &msq->q_messages, m_list) { if (testmsg(msg, *msgtyp, mode) && !security_msg_queue_msgrcv(msq, msg, current, *msgtyp, mode)) { if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) { *msgtyp = msg->m_type - 1; } else if (mode == SEARCH_NUMBER) { if (*msgtyp == count) return msg; } else return msg; count++; } } return ERR_PTR(-EAGAIN); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,624
static inline void free_copy(struct msg_msg *copy) { if (copy) free_msg(copy); }
DoS
0
static inline void free_copy(struct msg_msg *copy) { if (copy) free_msg(copy); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,625
static inline void free_copy(struct msg_msg *copy) { }
DoS
0
static inline void free_copy(struct msg_msg *copy) { }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,626
void msg_exit_ns(struct ipc_namespace *ns) { free_ipcs(ns, &msg_ids(ns), freeque); idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr); }
DoS
0
void msg_exit_ns(struct ipc_namespace *ns) { free_ipcs(ns, &msg_ids(ns), freeque); idr_destroy(&ns->ids[IPC_MSG_IDS].ipcs_idr); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,627
void __init msg_init(void) { msg_init_ns(&init_ipc_ns); printk(KERN_INFO "msgmni has been set to %d\n", init_ipc_ns.msg_ctlmni); ipc_init_proc_interface("sysvipc/msg", " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n", IPC_MSG_IDS, sysvipc_msg_proc_show); }
DoS
0
void __init msg_init(void) { msg_init_ns(&init_ipc_ns); printk(KERN_INFO "msgmni has been set to %d\n", init_ipc_ns.msg_ctlmni); ipc_init_proc_interface("sysvipc/msg", " key msqid perms cbytes qnum lspid lrpid uid gid cuid cgid stime rtime ctime\n", IPC_MSG_IDS, sysvipc_msg_proc_show); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,628
void msg_init_ns(struct ipc_namespace *ns) { ns->msg_ctlmax = MSGMAX; ns->msg_ctlmnb = MSGMNB; recompute_msgmni(ns); atomic_set(&ns->msg_bytes, 0); atomic_set(&ns->msg_hdrs, 0); ipc_init_ids(&ns->ids[IPC_MSG_IDS]); }
DoS
0
void msg_init_ns(struct ipc_namespace *ns) { ns->msg_ctlmax = MSGMAX; ns->msg_ctlmnb = MSGMNB; recompute_msgmni(ns); atomic_set(&ns->msg_bytes, 0); atomic_set(&ns->msg_hdrs, 0); ipc_init_ids(&ns->ids[IPC_MSG_IDS]); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,629
static inline struct msg_queue *msg_lock(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_lock(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm); }
DoS
0
static inline struct msg_queue *msg_lock(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_lock(&msg_ids(ns), id); if (IS_ERR(ipcp)) return (struct msg_queue *)ipcp; return container_of(ipcp, struct msg_queue, q_perm); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,630
static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s) { ipc_rmid(&msg_ids(ns), &s->q_perm); }
DoS
0
static inline void msg_rmid(struct ipc_namespace *ns, struct msg_queue *s) { ipc_rmid(&msg_ids(ns), &s->q_perm); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,631
static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg) { struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); return security_msg_queue_associate(msq, msgflg); }
DoS
0
static inline int msg_security(struct kern_ipc_perm *ipcp, int msgflg) { struct msg_queue *msq = container_of(ipcp, struct msg_queue, q_perm); return security_msg_queue_associate(msq, msgflg); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,632
static int newque(struct ipc_namespace *ns, struct ipc_params *params) { struct msg_queue *msq; int id, retval; key_t key = params->key; int msgflg = params->flg; msq = ipc_rcu_alloc(sizeof(*msq)); if (!msq) return -ENOMEM; msq->q_perm.mode = msgflg & S_IRWXUGO; msq->q_perm.key = key; msq->q_perm.security = NULL; retval = security_msg_queue_alloc(msq); if (retval) { ipc_rcu_putref(msq); return retval; } /* * ipc_addid() locks msq */ id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni); if (id < 0) { security_msg_queue_free(msq); ipc_rcu_putref(msq); return id; } msq->q_stime = msq->q_rtime = 0; msq->q_ctime = get_seconds(); msq->q_cbytes = msq->q_qnum = 0; msq->q_qbytes = ns->msg_ctlmnb; msq->q_lspid = msq->q_lrpid = 0; INIT_LIST_HEAD(&msq->q_messages); INIT_LIST_HEAD(&msq->q_receivers); INIT_LIST_HEAD(&msq->q_senders); msg_unlock(msq); return msq->q_perm.id; }
DoS
0
static int newque(struct ipc_namespace *ns, struct ipc_params *params) { struct msg_queue *msq; int id, retval; key_t key = params->key; int msgflg = params->flg; msq = ipc_rcu_alloc(sizeof(*msq)); if (!msq) return -ENOMEM; msq->q_perm.mode = msgflg & S_IRWXUGO; msq->q_perm.key = key; msq->q_perm.security = NULL; retval = security_msg_queue_alloc(msq); if (retval) { ipc_rcu_putref(msq); return retval; } /* * ipc_addid() locks msq */ id = ipc_addid(&msg_ids(ns), &msq->q_perm, ns->msg_ctlmni); if (id < 0) { security_msg_queue_free(msq); ipc_rcu_putref(msq); return id; } msq->q_stime = msq->q_rtime = 0; msq->q_ctime = get_seconds(); msq->q_cbytes = msq->q_qnum = 0; msq->q_qbytes = ns->msg_ctlmnb; msq->q_lspid = msq->q_lrpid = 0; INIT_LIST_HEAD(&msq->q_messages); INIT_LIST_HEAD(&msq->q_receivers); INIT_LIST_HEAD(&msq->q_senders); msg_unlock(msq); return msq->q_perm.id; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,633
static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg) { struct list_head *tmp; tmp = msq->q_receivers.next; while (tmp != &msq->q_receivers) { struct msg_receiver *msr; msr = list_entry(tmp, struct msg_receiver, r_list); tmp = tmp->next; if (testmsg(msg, msr->r_msgtype, msr->r_mode) && !security_msg_queue_msgrcv(msq, msg, msr->r_tsk, msr->r_msgtype, msr->r_mode)) { list_del(&msr->r_list); if (msr->r_maxsize < msg->m_ts) { msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(-E2BIG); } else { msr->r_msg = NULL; msq->q_lrpid = task_pid_vnr(msr->r_tsk); msq->q_rtime = get_seconds(); wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = msg; return 1; } } } return 0; }
DoS
0
static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg) { struct list_head *tmp; tmp = msq->q_receivers.next; while (tmp != &msq->q_receivers) { struct msg_receiver *msr; msr = list_entry(tmp, struct msg_receiver, r_list); tmp = tmp->next; if (testmsg(msg, msr->r_msgtype, msr->r_mode) && !security_msg_queue_msgrcv(msq, msg, msr->r_tsk, msr->r_msgtype, msr->r_mode)) { list_del(&msr->r_list); if (msr->r_maxsize < msg->m_ts) { msr->r_msg = NULL; wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = ERR_PTR(-E2BIG); } else { msr->r_msg = NULL; msq->q_lrpid = task_pid_vnr(msr->r_tsk); msq->q_rtime = get_seconds(); wake_up_process(msr->r_tsk); smp_mb(); msr->r_msg = msg; return 1; } } } return 0; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,634
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz) { struct msg_msg *copy; /* * Create dummy message to copy real message to. */ copy = load_msg(buf, bufsz); if (!IS_ERR(copy)) copy->m_ts = bufsz; return copy; }
DoS
0
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz) { struct msg_msg *copy; /* * Create dummy message to copy real message to. */ copy = load_msg(buf, bufsz); if (!IS_ERR(copy)) copy->m_ts = bufsz; return copy; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,635
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz) { return ERR_PTR(-ENOSYS); }
DoS
0
static inline struct msg_msg *prepare_copy(void __user *buf, size_t bufsz) { return ERR_PTR(-ENOSYS); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,636
void recompute_msgmni(struct ipc_namespace *ns) { struct sysinfo i; unsigned long allowed; int nb_ns; si_meminfo(&i); allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit) / MSGMNB; nb_ns = atomic_read(&nr_ipc_ns); allowed /= nb_ns; if (allowed < MSGMNI) { ns->msg_ctlmni = MSGMNI; return; } if (allowed > IPCMNI / nb_ns) { ns->msg_ctlmni = IPCMNI / nb_ns; return; } ns->msg_ctlmni = allowed; }
DoS
0
void recompute_msgmni(struct ipc_namespace *ns) { struct sysinfo i; unsigned long allowed; int nb_ns; si_meminfo(&i); allowed = (((i.totalram - i.totalhigh) / MSG_MEM_SCALE) * i.mem_unit) / MSGMNB; nb_ns = atomic_read(&nr_ipc_ns); allowed /= nb_ns; if (allowed < MSGMNI) { ns->msg_ctlmni = MSGMNI; return; } if (allowed > IPCMNI / nb_ns) { ns->msg_ctlmni = IPCMNI / nb_ns; return; } ns->msg_ctlmni = allowed; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,637
static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss) { mss->tsk = current; current->state = TASK_INTERRUPTIBLE; list_add_tail(&mss->list, &msq->q_senders); }
DoS
0
static inline void ss_add(struct msg_queue *msq, struct msg_sender *mss) { mss->tsk = current; current->state = TASK_INTERRUPTIBLE; list_add_tail(&mss->list, &msq->q_senders); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,638
static int sysvipc_msg_proc_show(struct seq_file *s, void *it) { struct user_namespace *user_ns = seq_user_ns(s); struct msg_queue *msq = it; return seq_printf(s, "%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n", msq->q_perm.key, msq->q_perm.id, msq->q_perm.mode, msq->q_cbytes, msq->q_qnum, msq->q_lspid, msq->q_lrpid, from_kuid_munged(user_ns, msq->q_perm.uid), from_kgid_munged(user_ns, msq->q_perm.gid), from_kuid_munged(user_ns, msq->q_perm.cuid), from_kgid_munged(user_ns, msq->q_perm.cgid), msq->q_stime, msq->q_rtime, msq->q_ctime); }
DoS
0
static int sysvipc_msg_proc_show(struct seq_file *s, void *it) { struct user_namespace *user_ns = seq_user_ns(s); struct msg_queue *msq = it; return seq_printf(s, "%10d %10d %4o %10lu %10lu %5u %5u %5u %5u %5u %5u %10lu %10lu %10lu\n", msq->q_perm.key, msq->q_perm.id, msq->q_perm.mode, msq->q_cbytes, msq->q_qnum, msq->q_lspid, msq->q_lrpid, from_kuid_munged(user_ns, msq->q_perm.uid), from_kgid_munged(user_ns, msq->q_perm.gid), from_kuid_munged(user_ns, msq->q_perm.cuid), from_kgid_munged(user_ns, msq->q_perm.cgid), msq->q_stime, msq->q_rtime, msq->q_ctime); }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,639
static int testmsg(struct msg_msg *msg, long type, int mode) { switch(mode) { case SEARCH_ANY: case SEARCH_NUMBER: return 1; case SEARCH_LESSEQUAL: if (msg->m_type <=type) return 1; break; case SEARCH_EQUAL: if (msg->m_type == type) return 1; break; case SEARCH_NOTEQUAL: if (msg->m_type != type) return 1; break; } return 0; }
DoS
0
static int testmsg(struct msg_msg *msg, long type, int mode) { switch(mode) { case SEARCH_ANY: case SEARCH_NUMBER: return 1; case SEARCH_LESSEQUAL: if (msg->m_type <=type) return 1; break; case SEARCH_EQUAL: if (msg->m_type == type) return 1; break; case SEARCH_NOTEQUAL: if (msg->m_type != type) return 1; break; } return 0; }
@@ -687,7 +687,12 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, goto out_unlock_free; } ss_add(msq, &s); - ipc_rcu_getref(msq); + + if (!ipc_rcu_getref(msq)) { + err = -EIDRM; + goto out_unlock_free; + } + msg_unlock(msq); schedule();
CWE-189
null
null
23,640
SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) { struct ipc_namespace *ns; struct ipc_ops sem_ops; struct ipc_params sem_params; ns = current->nsproxy->ipc_ns; if (nsems < 0 || nsems > ns->sc_semmsl) return -EINVAL; sem_ops.getnew = newary; sem_ops.associate = sem_security; sem_ops.more_checks = sem_more_checks; sem_params.key = key; sem_params.flg = semflg; sem_params.u.nsems = nsems; return ipcget(ns, &sem_ids(ns), &sem_ops, &sem_params); }
DoS
0
SYSCALL_DEFINE3(semget, key_t, key, int, nsems, int, semflg) { struct ipc_namespace *ns; struct ipc_ops sem_ops; struct ipc_params sem_params; ns = current->nsproxy->ipc_ns; if (nsems < 0 || nsems > ns->sc_semmsl) return -EINVAL; sem_ops.getnew = newary; sem_ops.associate = sem_security; sem_ops.more_checks = sem_more_checks; sem_params.key = key; sem_params.flg = semflg; sem_params.u.nsems = nsems; return ipcget(ns, &sem_ids(ns), &sem_ops, &sem_params); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,641
SYSCALL_DEFINE3(semop, int, semid, struct sembuf __user *, tsops, unsigned, nsops) { return sys_semtimedop(semid, tsops, nsops, NULL); }
DoS
0
SYSCALL_DEFINE3(semop, int, semid, struct sembuf __user *, tsops, unsigned, nsops) { return sys_semtimedop(semid, tsops, nsops, NULL); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,642
SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg) { int version; struct ipc_namespace *ns; void __user *p = (void __user *)arg; if (semid < 0) return -EINVAL; version = ipc_parse_version(&cmd); ns = current->nsproxy->ipc_ns; switch(cmd) { case IPC_INFO: case SEM_INFO: case IPC_STAT: case SEM_STAT: return semctl_nolock(ns, semid, cmd, version, p); case GETALL: case GETVAL: case GETPID: case GETNCNT: case GETZCNT: case SETALL: return semctl_main(ns, semid, semnum, cmd, p); case SETVAL: return semctl_setval(ns, semid, semnum, arg); case IPC_RMID: case IPC_SET: return semctl_down(ns, semid, cmd, version, p); default: return -EINVAL; } }
DoS
0
SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg) { int version; struct ipc_namespace *ns; void __user *p = (void __user *)arg; if (semid < 0) return -EINVAL; version = ipc_parse_version(&cmd); ns = current->nsproxy->ipc_ns; switch(cmd) { case IPC_INFO: case SEM_INFO: case IPC_STAT: case SEM_STAT: return semctl_nolock(ns, semid, cmd, version, p); case GETALL: case GETVAL: case GETPID: case GETNCNT: case GETZCNT: case SETALL: return semctl_main(ns, semid, semnum, cmd, p); case SETVAL: return semctl_setval(ns, semid, semnum, arg); case IPC_RMID: case IPC_SET: return semctl_down(ns, semid, cmd, version, p); default: return -EINVAL; } }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,643
static int check_restart(struct sem_array *sma, struct sem_queue *q) { struct sem *curr; struct sem_queue *h; /* if the operation didn't modify the array, then no restart */ if (q->alter == 0) return 0; /* pending complex operations are too difficult to analyse */ if (sma->complex_count) return 1; /* we were a sleeping complex operation. Too difficult */ if (q->nsops > 1) return 1; curr = sma->sem_base + q->sops[0].sem_num; /* No-one waits on this queue */ if (list_empty(&curr->sem_pending)) return 0; /* the new semaphore value */ if (curr->semval) { /* It is impossible that someone waits for the new value: * - q is a previously sleeping simple operation that * altered the array. It must be a decrement, because * simple increments never sleep. * - The value is not 0, thus wait-for-zero won't proceed. * - If there are older (higher priority) decrements * in the queue, then they have observed the original * semval value and couldn't proceed. The operation * decremented to value - thus they won't proceed either. */ BUG_ON(q->sops[0].sem_op >= 0); return 0; } /* * semval is 0. Check if there are wait-for-zero semops. * They must be the first entries in the per-semaphore queue */ h = list_first_entry(&curr->sem_pending, struct sem_queue, list); BUG_ON(h->nsops != 1); BUG_ON(h->sops[0].sem_num != q->sops[0].sem_num); /* Yes, there is a wait-for-zero semop. Restart */ if (h->sops[0].sem_op == 0) return 1; /* Again - no-one is waiting for the new value. */ return 0; }
DoS
0
static int check_restart(struct sem_array *sma, struct sem_queue *q) { struct sem *curr; struct sem_queue *h; /* if the operation didn't modify the array, then no restart */ if (q->alter == 0) return 0; /* pending complex operations are too difficult to analyse */ if (sma->complex_count) return 1; /* we were a sleeping complex operation. Too difficult */ if (q->nsops > 1) return 1; curr = sma->sem_base + q->sops[0].sem_num; /* No-one waits on this queue */ if (list_empty(&curr->sem_pending)) return 0; /* the new semaphore value */ if (curr->semval) { /* It is impossible that someone waits for the new value: * - q is a previously sleeping simple operation that * altered the array. It must be a decrement, because * simple increments never sleep. * - The value is not 0, thus wait-for-zero won't proceed. * - If there are older (higher priority) decrements * in the queue, then they have observed the original * semval value and couldn't proceed. The operation * decremented to value - thus they won't proceed either. */ BUG_ON(q->sops[0].sem_op >= 0); return 0; } /* * semval is 0. Check if there are wait-for-zero semops. * They must be the first entries in the per-semaphore queue */ h = list_first_entry(&curr->sem_pending, struct sem_queue, list); BUG_ON(h->nsops != 1); BUG_ON(h->sops[0].sem_num != q->sops[0].sem_num); /* Yes, there is a wait-for-zero semop. Restart */ if (h->sops[0].sem_op == 0) return 1; /* Again - no-one is waiting for the new value. */ return 0; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,644
static unsigned long copy_semid_to_user(void __user *buf, struct semid64_ds *in, int version) { switch(version) { case IPC_64: return copy_to_user(buf, in, sizeof(*in)); case IPC_OLD: { struct semid_ds out; memset(&out, 0, sizeof(out)); ipc64_perm_to_ipc_perm(&in->sem_perm, &out.sem_perm); out.sem_otime = in->sem_otime; out.sem_ctime = in->sem_ctime; out.sem_nsems = in->sem_nsems; return copy_to_user(buf, &out, sizeof(out)); } default: return -EINVAL; } }
DoS
0
static unsigned long copy_semid_to_user(void __user *buf, struct semid64_ds *in, int version) { switch(version) { case IPC_64: return copy_to_user(buf, in, sizeof(*in)); case IPC_OLD: { struct semid_ds out; memset(&out, 0, sizeof(out)); ipc64_perm_to_ipc_perm(&in->sem_perm, &out.sem_perm); out.sem_otime = in->sem_otime; out.sem_ctime = in->sem_ctime; out.sem_nsems = in->sem_nsems; return copy_to_user(buf, &out, sizeof(out)); } default: return -EINVAL; } }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,645
int copy_semundo(unsigned long clone_flags, struct task_struct *tsk) { struct sem_undo_list *undo_list; int error; if (clone_flags & CLONE_SYSVSEM) { error = get_undo_list(&undo_list); if (error) return error; atomic_inc(&undo_list->refcnt); tsk->sysvsem.undo_list = undo_list; } else tsk->sysvsem.undo_list = NULL; return 0; }
DoS
0
int copy_semundo(unsigned long clone_flags, struct task_struct *tsk) { struct sem_undo_list *undo_list; int error; if (clone_flags & CLONE_SYSVSEM) { error = get_undo_list(&undo_list); if (error) return error; atomic_inc(&undo_list->refcnt); tsk->sysvsem.undo_list = undo_list; } else tsk->sysvsem.undo_list = NULL; return 0; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,646
static int count_semncnt (struct sem_array * sma, ushort semnum) { int semncnt; struct sem_queue * q; semncnt = 0; list_for_each_entry(q, &sma->sem_pending, list) { struct sembuf * sops = q->sops; int nsops = q->nsops; int i; for (i = 0; i < nsops; i++) if (sops[i].sem_num == semnum && (sops[i].sem_op < 0) && !(sops[i].sem_flg & IPC_NOWAIT)) semncnt++; } return semncnt; }
DoS
0
static int count_semncnt (struct sem_array * sma, ushort semnum) { int semncnt; struct sem_queue * q; semncnt = 0; list_for_each_entry(q, &sma->sem_pending, list) { struct sembuf * sops = q->sops; int nsops = q->nsops; int i; for (i = 0; i < nsops; i++) if (sops[i].sem_num == semnum && (sops[i].sem_op < 0) && !(sops[i].sem_flg & IPC_NOWAIT)) semncnt++; } return semncnt; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,647
static int count_semzcnt (struct sem_array * sma, ushort semnum) { int semzcnt; struct sem_queue * q; semzcnt = 0; list_for_each_entry(q, &sma->sem_pending, list) { struct sembuf * sops = q->sops; int nsops = q->nsops; int i; for (i = 0; i < nsops; i++) if (sops[i].sem_num == semnum && (sops[i].sem_op == 0) && !(sops[i].sem_flg & IPC_NOWAIT)) semzcnt++; } return semzcnt; }
DoS
0
static int count_semzcnt (struct sem_array * sma, ushort semnum) { int semzcnt; struct sem_queue * q; semzcnt = 0; list_for_each_entry(q, &sma->sem_pending, list) { struct sembuf * sops = q->sops; int nsops = q->nsops; int i; for (i = 0; i < nsops; i++) if (sops[i].sem_num == semnum && (sops[i].sem_op == 0) && !(sops[i].sem_flg & IPC_NOWAIT)) semzcnt++; } return semzcnt; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,648
static int get_queue_result(struct sem_queue *q) { int error; error = q->status; while (unlikely(error == IN_WAKEUP)) { cpu_relax(); error = q->status; } return error; }
DoS
0
static int get_queue_result(struct sem_queue *q) { int error; error = q->status; while (unlikely(error == IN_WAKEUP)) { cpu_relax(); error = q->status; } return error; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,649
static inline int get_undo_list(struct sem_undo_list **undo_listp) { struct sem_undo_list *undo_list; undo_list = current->sysvsem.undo_list; if (!undo_list) { undo_list = kzalloc(sizeof(*undo_list), GFP_KERNEL); if (undo_list == NULL) return -ENOMEM; spin_lock_init(&undo_list->lock); atomic_set(&undo_list->refcnt, 1); INIT_LIST_HEAD(&undo_list->list_proc); current->sysvsem.undo_list = undo_list; } *undo_listp = undo_list; return 0; }
DoS
0
static inline int get_undo_list(struct sem_undo_list **undo_listp) { struct sem_undo_list *undo_list; undo_list = current->sysvsem.undo_list; if (!undo_list) { undo_list = kzalloc(sizeof(*undo_list), GFP_KERNEL); if (undo_list == NULL) return -ENOMEM; spin_lock_init(&undo_list->lock); atomic_set(&undo_list->refcnt, 1); INIT_LIST_HEAD(&undo_list->list_proc); current->sysvsem.undo_list = undo_list; } *undo_listp = undo_list; return 0; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,650
static struct sem_undo *lookup_undo(struct sem_undo_list *ulp, int semid) { struct sem_undo *un; assert_spin_locked(&ulp->lock); un = __lookup_undo(ulp, semid); if (un) { list_del_rcu(&un->list_proc); list_add_rcu(&un->list_proc, &ulp->list_proc); } return un; }
DoS
0
static struct sem_undo *lookup_undo(struct sem_undo_list *ulp, int semid) { struct sem_undo *un; assert_spin_locked(&ulp->lock); un = __lookup_undo(ulp, semid); if (un) { list_del_rcu(&un->list_proc); list_add_rcu(&un->list_proc, &ulp->list_proc); } return un; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,651
void sem_exit_ns(struct ipc_namespace *ns) { free_ipcs(ns, &sem_ids(ns), freeary); idr_destroy(&ns->ids[IPC_SEM_IDS].ipcs_idr); }
DoS
0
void sem_exit_ns(struct ipc_namespace *ns) { free_ipcs(ns, &sem_ids(ns), freeary); idr_destroy(&ns->ids[IPC_SEM_IDS].ipcs_idr); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,652
void sem_init_ns(struct ipc_namespace *ns) { ns->sc_semmsl = SEMMSL; ns->sc_semmns = SEMMNS; ns->sc_semopm = SEMOPM; ns->sc_semmni = SEMMNI; ns->used_sems = 0; ipc_init_ids(&ns->ids[IPC_SEM_IDS]); }
DoS
0
void sem_init_ns(struct ipc_namespace *ns) { ns->sc_semmsl = SEMMSL; ns->sc_semmns = SEMMNS; ns->sc_semopm = SEMOPM; ns->sc_semmni = SEMMNI; ns->used_sems = 0; ipc_init_ids(&ns->ids[IPC_SEM_IDS]); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,653
static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_obtain_object(&sem_ids(ns), id); if (IS_ERR(ipcp)) return ERR_CAST(ipcp); return container_of(ipcp, struct sem_array, sem_perm); }
DoS
0
static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_obtain_object(&sem_ids(ns), id); if (IS_ERR(ipcp)) return ERR_CAST(ipcp); return container_of(ipcp, struct sem_array, sem_perm); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,654
static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&sem_ids(ns), id); if (IS_ERR(ipcp)) return ERR_CAST(ipcp); return container_of(ipcp, struct sem_array, sem_perm); }
DoS
0
static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&sem_ids(ns), id); if (IS_ERR(ipcp)) return ERR_CAST(ipcp); return container_of(ipcp, struct sem_array, sem_perm); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,655
static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) { ipc_rmid(&sem_ids(ns), &s->sem_perm); }
DoS
0
static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) { ipc_rmid(&sem_ids(ns), &s->sem_perm); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,656
static inline int sem_security(struct kern_ipc_perm *ipcp, int semflg) { struct sem_array *sma; sma = container_of(ipcp, struct sem_array, sem_perm); return security_sem_associate(sma, semflg); }
DoS
0
static inline int sem_security(struct kern_ipc_perm *ipcp, int semflg) { struct sem_array *sma; sma = container_of(ipcp, struct sem_array, sem_perm); return security_sem_associate(sma, semflg); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,657
static int sysvipc_sem_proc_show(struct seq_file *s, void *it) { struct user_namespace *user_ns = seq_user_ns(s); struct sem_array *sma = it; return seq_printf(s, "%10d %10d %4o %10u %5u %5u %5u %5u %10lu %10lu\n", sma->sem_perm.key, sma->sem_perm.id, sma->sem_perm.mode, sma->sem_nsems, from_kuid_munged(user_ns, sma->sem_perm.uid), from_kgid_munged(user_ns, sma->sem_perm.gid), from_kuid_munged(user_ns, sma->sem_perm.cuid), from_kgid_munged(user_ns, sma->sem_perm.cgid), sma->sem_otime, sma->sem_ctime); }
DoS
0
static int sysvipc_sem_proc_show(struct seq_file *s, void *it) { struct user_namespace *user_ns = seq_user_ns(s); struct sem_array *sma = it; return seq_printf(s, "%10d %10d %4o %10u %5u %5u %5u %5u %10lu %10lu\n", sma->sem_perm.key, sma->sem_perm.id, sma->sem_perm.mode, sma->sem_nsems, from_kuid_munged(user_ns, sma->sem_perm.uid), from_kgid_munged(user_ns, sma->sem_perm.gid), from_kuid_munged(user_ns, sma->sem_perm.cuid), from_kgid_munged(user_ns, sma->sem_perm.cgid), sma->sem_otime, sma->sem_ctime); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,658
static int try_atomic_semop (struct sem_array * sma, struct sembuf * sops, int nsops, struct sem_undo *un, int pid) { int result, sem_op; struct sembuf *sop; struct sem * curr; for (sop = sops; sop < sops + nsops; sop++) { curr = sma->sem_base + sop->sem_num; sem_op = sop->sem_op; result = curr->semval; if (!sem_op && result) goto would_block; result += sem_op; if (result < 0) goto would_block; if (result > SEMVMX) goto out_of_range; if (sop->sem_flg & SEM_UNDO) { int undo = un->semadj[sop->sem_num] - sem_op; /* * Exceeding the undo range is an error. */ if (undo < (-SEMAEM - 1) || undo > SEMAEM) goto out_of_range; } curr->semval = result; } sop--; while (sop >= sops) { sma->sem_base[sop->sem_num].sempid = pid; if (sop->sem_flg & SEM_UNDO) un->semadj[sop->sem_num] -= sop->sem_op; sop--; } return 0; out_of_range: result = -ERANGE; goto undo; would_block: if (sop->sem_flg & IPC_NOWAIT) result = -EAGAIN; else result = 1; undo: sop--; while (sop >= sops) { sma->sem_base[sop->sem_num].semval -= sop->sem_op; sop--; } return result; }
DoS
0
static int try_atomic_semop (struct sem_array * sma, struct sembuf * sops, int nsops, struct sem_undo *un, int pid) { int result, sem_op; struct sembuf *sop; struct sem * curr; for (sop = sops; sop < sops + nsops; sop++) { curr = sma->sem_base + sop->sem_num; sem_op = sop->sem_op; result = curr->semval; if (!sem_op && result) goto would_block; result += sem_op; if (result < 0) goto would_block; if (result > SEMVMX) goto out_of_range; if (sop->sem_flg & SEM_UNDO) { int undo = un->semadj[sop->sem_num] - sem_op; /* * Exceeding the undo range is an error. */ if (undo < (-SEMAEM - 1) || undo > SEMAEM) goto out_of_range; } curr->semval = result; } sop--; while (sop >= sops) { sma->sem_base[sop->sem_num].sempid = pid; if (sop->sem_flg & SEM_UNDO) un->semadj[sop->sem_num] -= sop->sem_op; sop--; } return 0; out_of_range: result = -ERANGE; goto undo; would_block: if (sop->sem_flg & IPC_NOWAIT) result = -EAGAIN; else result = 1; undo: sop--; while (sop >= sops) { sma->sem_base[sop->sem_num].semval -= sop->sem_op; sop--; } return result; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,659
static void unlink_queue(struct sem_array *sma, struct sem_queue *q) { list_del(&q->list); if (q->nsops > 1) sma->complex_count--; }
DoS
0
static void unlink_queue(struct sem_array *sma, struct sem_queue *q) { list_del(&q->list); if (q->nsops > 1) sma->complex_count--; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,660
static int update_queue(struct sem_array *sma, int semnum, struct list_head *pt) { struct sem_queue *q; struct list_head *walk; struct list_head *pending_list; int semop_completed = 0; if (semnum == -1) pending_list = &sma->sem_pending; else pending_list = &sma->sem_base[semnum].sem_pending; again: walk = pending_list->next; while (walk != pending_list) { int error, restart; q = container_of(walk, struct sem_queue, list); walk = walk->next; /* If we are scanning the single sop, per-semaphore list of * one semaphore and that semaphore is 0, then it is not * necessary to scan the "alter" entries: simple increments * that affect only one entry succeed immediately and cannot * be in the per semaphore pending queue, and decrements * cannot be successful if the value is already 0. */ if (semnum != -1 && sma->sem_base[semnum].semval == 0 && q->alter) break; error = try_atomic_semop(sma, q->sops, q->nsops, q->undo, q->pid); /* Does q->sleeper still need to sleep? */ if (error > 0) continue; unlink_queue(sma, q); if (error) { restart = 0; } else { semop_completed = 1; restart = check_restart(sma, q); } wake_up_sem_queue_prepare(pt, q, error); if (restart) goto again; } return semop_completed; }
DoS
0
static int update_queue(struct sem_array *sma, int semnum, struct list_head *pt) { struct sem_queue *q; struct list_head *walk; struct list_head *pending_list; int semop_completed = 0; if (semnum == -1) pending_list = &sma->sem_pending; else pending_list = &sma->sem_base[semnum].sem_pending; again: walk = pending_list->next; while (walk != pending_list) { int error, restart; q = container_of(walk, struct sem_queue, list); walk = walk->next; /* If we are scanning the single sop, per-semaphore list of * one semaphore and that semaphore is 0, then it is not * necessary to scan the "alter" entries: simple increments * that affect only one entry succeed immediately and cannot * be in the per semaphore pending queue, and decrements * cannot be successful if the value is already 0. */ if (semnum != -1 && sma->sem_base[semnum].semval == 0 && q->alter) break; error = try_atomic_semop(sma, q->sops, q->nsops, q->undo, q->pid); /* Does q->sleeper still need to sleep? */ if (error > 0) continue; unlink_queue(sma, q); if (error) { restart = 0; } else { semop_completed = 1; restart = check_restart(sma, q); } wake_up_sem_queue_prepare(pt, q, error); if (restart) goto again; } return semop_completed; }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,661
static void wake_up_sem_queue_do(struct list_head *pt) { struct sem_queue *q, *t; int did_something; did_something = !list_empty(pt); list_for_each_entry_safe(q, t, pt, list) { wake_up_process(q->sleeper); /* q can disappear immediately after writing q->status. */ smp_wmb(); q->status = q->pid; } if (did_something) preempt_enable(); }
DoS
0
static void wake_up_sem_queue_do(struct list_head *pt) { struct sem_queue *q, *t; int did_something; did_something = !list_empty(pt); list_for_each_entry_safe(q, t, pt, list) { wake_up_process(q->sleeper); /* q can disappear immediately after writing q->status. */ smp_wmb(); q->status = q->pid; } if (did_something) preempt_enable(); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,662
static void wake_up_sem_queue_prepare(struct list_head *pt, struct sem_queue *q, int error) { if (list_empty(pt)) { /* * Hold preempt off so that we don't get preempted and have the * wakee busy-wait until we're scheduled back on. */ preempt_disable(); } q->status = IN_WAKEUP; q->pid = error; list_add_tail(&q->list, pt); }
DoS
0
static void wake_up_sem_queue_prepare(struct list_head *pt, struct sem_queue *q, int error) { if (list_empty(pt)) { /* * Hold preempt off so that we don't get preempted and have the * wakee busy-wait until we're scheduled back on. */ preempt_disable(); } q->status = IN_WAKEUP; q->pid = error; list_add_tail(&q->list, pt); }
@@ -94,6 +94,7 @@ struct sem { int semval; /* current value */ int sempid; /* pid of last operation */ + spinlock_t lock; /* spinlock for fine-grained semtimedop */ struct list_head sem_pending; /* pending single-sop operations */ }; @@ -137,7 +138,6 @@ struct sem_undo_list { #define sem_ids(ns) ((ns)->ids[IPC_SEM_IDS]) -#define sem_unlock(sma) ipc_unlock(&(sma)->sem_perm) #define sem_checkid(sma, semid) ipc_checkid(&sma->sem_perm, semid) static int newary(struct ipc_namespace *, struct ipc_params *); @@ -189,11 +189,90 @@ void __init sem_init (void) IPC_SEM_IDS, sysvipc_sem_proc_show); } +/* + * If the request contains only one semaphore operation, and there are + * no complex transactions pending, lock only the semaphore involved. + * Otherwise, lock the entire semaphore array, since we either have + * multiple semaphores in our own semops, or we need to look at + * semaphores from other pending complex operations. + * + * Carefully guard against sma->complex_count changing between zero + * and non-zero while we are spinning for the lock. The value of + * sma->complex_count cannot change while we are holding the lock, + * so sem_unlock should be fine. + * + * The global lock path checks that all the local locks have been released, + * checking each local lock once. This means that the local lock paths + * cannot start their critical sections while the global lock is held. + */ +static inline int sem_lock(struct sem_array *sma, struct sembuf *sops, + int nsops) +{ + int locknum; + again: + if (nsops == 1 && !sma->complex_count) { + struct sem *sem = sma->sem_base + sops->sem_num; + + /* Lock just the semaphore we are interested in. */ + spin_lock(&sem->lock); + + /* + * If sma->complex_count was set while we were spinning, + * we may need to look at things we did not lock here. + */ + if (unlikely(sma->complex_count)) { + spin_unlock(&sem->lock); + goto lock_array; + } + + /* + * Another process is holding the global lock on the + * sem_array; we cannot enter our critical section, + * but have to wait for the global lock to be released. + */ + if (unlikely(spin_is_locked(&sma->sem_perm.lock))) { + spin_unlock(&sem->lock); + spin_unlock_wait(&sma->sem_perm.lock); + goto again; + } + + locknum = sops->sem_num; + } else { + int i; + /* + * Lock the semaphore array, and wait for all of the + * individual semaphore locks to go away. The code + * above ensures no new single-lock holders will enter + * their critical section while the array lock is held. + */ + lock_array: + spin_lock(&sma->sem_perm.lock); + for (i = 0; i < sma->sem_nsems; i++) { + struct sem *sem = sma->sem_base + i; + spin_unlock_wait(&sem->lock); + } + locknum = -1; + } + return locknum; +} + +static inline void sem_unlock(struct sem_array *sma, int locknum) +{ + if (locknum == -1) { + spin_unlock(&sma->sem_perm.lock); + } else { + struct sem *sem = sma->sem_base + locknum; + spin_unlock(&sem->lock); + } + rcu_read_unlock(); +} + /* * sem_lock_(check_) routines are called in the paths where the rw_mutex * is not held. */ -static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id) +static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, + int id, struct sembuf *sops, int nsops, int *locknum) { struct kern_ipc_perm *ipcp; struct sem_array *sma; @@ -205,15 +284,16 @@ static inline struct sem_array *sem_obtain_lock(struct ipc_namespace *ns, int id goto err; } - spin_lock(&ipcp->lock); + sma = container_of(ipcp, struct sem_array, sem_perm); + *locknum = sem_lock(sma, sops, nsops); /* ipc_rmid() may have already freed the ID while sem_lock * was spinning: verify that the structure is still valid */ if (!ipcp->deleted) return container_of(ipcp, struct sem_array, sem_perm); - spin_unlock(&ipcp->lock); + sem_unlock(sma, *locknum); sma = ERR_PTR(-EINVAL); err: rcu_read_unlock(); @@ -230,17 +310,6 @@ static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int return container_of(ipcp, struct sem_array, sem_perm); } -static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns, - int id) -{ - struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id); - - if (IS_ERR(ipcp)) - return ERR_CAST(ipcp); - - return container_of(ipcp, struct sem_array, sem_perm); -} - static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns, int id) { @@ -254,31 +323,31 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); + rcu_read_lock(); + sem_lock(sma, NULL, -1); ipc_rcu_putref(sma); } static inline void sem_getref_and_unlock(struct sem_array *sma) { - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_putref(struct sem_array *sma) { - ipc_lock_by_ptr(&sma->sem_perm); - ipc_rcu_putref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock_and_putref(sma); + sem_unlock(sma, -1); } /* * Call inside the rcu read section. */ static inline void sem_getref(struct sem_array *sma) { - spin_lock(&(sma)->sem_perm.lock); - ipc_rcu_getref(sma); - ipc_unlock(&(sma)->sem_perm); + sem_lock(sma, NULL, -1); + WARN_ON_ONCE(!ipc_rcu_getref(sma)); + sem_unlock(sma, -1); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -371,15 +440,17 @@ static int newary(struct ipc_namespace *ns, struct ipc_params *params) sma->sem_base = (struct sem *) &sma[1]; - for (i = 0; i < nsems; i++) + for (i = 0; i < nsems; i++) { INIT_LIST_HEAD(&sma->sem_base[i].sem_pending); + spin_lock_init(&sma->sem_base[i].lock); + } sma->complex_count = 0; INIT_LIST_HEAD(&sma->sem_pending); INIT_LIST_HEAD(&sma->list_id); sma->sem_nsems = nsems; sma->sem_ctime = get_seconds(); - sem_unlock(sma); + sem_unlock(sma, -1); return sma->sem_perm.id; } @@ -818,7 +889,7 @@ static void freeary(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp) /* Remove the semaphore set from the IDR */ sem_rmid(ns, sma); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); ns->used_sems -= sma->sem_nsems; @@ -947,7 +1018,6 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, struct sem_array *sma; struct sem* curr; int err; - int nsems; struct list_head tasks; int val; #if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN) @@ -958,31 +1028,39 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, val = arg; #endif - sma = sem_lock_check(ns, semid); - if (IS_ERR(sma)) - return PTR_ERR(sma); + if (val > SEMVMX || val < 0) + return -ERANGE; INIT_LIST_HEAD(&tasks); - nsems = sma->sem_nsems; - err = -EACCES; - if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) - goto out_unlock; + rcu_read_lock(); + sma = sem_obtain_object_check(ns, semid); + if (IS_ERR(sma)) { + rcu_read_unlock(); + return PTR_ERR(sma); + } + + if (semnum < 0 || semnum >= sma->sem_nsems) { + rcu_read_unlock(); + return -EINVAL; + } + + + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) { + rcu_read_unlock(); + return -EACCES; + } err = security_sem_semctl(sma, SETVAL); - if (err) - goto out_unlock; + if (err) { + rcu_read_unlock(); + return -EACCES; + } - err = -EINVAL; - if(semnum < 0 || semnum >= nsems) - goto out_unlock; + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; - err = -ERANGE; - if (val > SEMVMX || val < 0) - goto out_unlock; - assert_spin_locked(&sma->sem_perm.lock); list_for_each_entry(un, &sma->list_id, list_id) un->semadj[semnum] = 0; @@ -992,11 +1070,9 @@ static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum, sma->sem_ctime = get_seconds(); /* maybe some queued-up processes were waiting for this */ do_smart_update(sma, NULL, 0, 0, &tasks); - err = 0; -out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); - return err; + return 0; } static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, @@ -1051,16 +1127,16 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } - } + } else + sem_lock(sma, NULL, -1); - spin_lock(&sma->sem_perm.lock); for (i = 0; i < sma->sem_nsems; i++) sem_io[i] = sma->sem_base[i].semval; - sem_unlock(sma); + sem_unlock(sma, -1); err = 0; if(copy_to_user(array, sem_io, nsems*sizeof(ushort))) err = -EFAULT; @@ -1071,7 +1147,10 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, int i; struct sem_undo *un; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + return -EIDRM; + } rcu_read_unlock(); if(nsems > SEMMSL_FAST) { @@ -1097,7 +1176,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); err = -EIDRM; goto out_free; } @@ -1124,7 +1203,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, goto out_wakeup; } - spin_lock(&sma->sem_perm.lock); + sem_lock(sma, NULL, -1); curr = &sma->sem_base[semnum]; switch (cmd) { @@ -1143,7 +1222,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1211,11 +1290,11 @@ static int semctl_down(struct ipc_namespace *ns, int semid, switch(cmd){ case IPC_RMID: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); freeary(ns, ipcp); goto out_up; case IPC_SET: - ipc_lock_object(&sma->sem_perm); + sem_lock(sma, NULL, -1); err = ipc_update_perm(&semid64.sem_perm, ipcp); if (err) goto out_unlock; @@ -1228,7 +1307,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, } out_unlock: - sem_unlock(sma); + sem_unlock(sma, -1); out_up: up_write(&sem_ids(ns).rw_mutex); return err; @@ -1340,8 +1419,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) struct sem_array *sma; struct sem_undo_list *ulp; struct sem_undo *un, *new; - int nsems; - int error; + int nsems, error; error = get_undo_list(&ulp); if (error) @@ -1363,7 +1441,11 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) } nsems = sma->sem_nsems; - ipc_rcu_getref(sma); + if (!ipc_rcu_getref(sma)) { + rcu_read_unlock(); + un = ERR_PTR(-EIDRM); + goto out; + } rcu_read_unlock(); /* step 2: allocate new undo structure */ @@ -1376,7 +1458,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 3: Acquire the lock on semaphore array */ sem_lock_and_putref(sma); if (sma->sem_perm.deleted) { - sem_unlock(sma); + sem_unlock(sma, -1); kfree(new); un = ERR_PTR(-EIDRM); goto out; @@ -1404,7 +1486,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) success: spin_unlock(&ulp->lock); rcu_read_lock(); - sem_unlock(sma); + sem_unlock(sma, -1); out: return un; } @@ -1444,7 +1526,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, struct sembuf fast_sops[SEMOPM_FAST]; struct sembuf* sops = fast_sops, *sop; struct sem_undo *un; - int undos = 0, alter = 0, max; + int undos = 0, alter = 0, max, locknum; struct sem_queue queue; unsigned long jiffies_left = 0; struct ipc_namespace *ns; @@ -1488,22 +1570,23 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, alter = 1; } + INIT_LIST_HEAD(&tasks); + if (undos) { + /* On success, find_alloc_undo takes the rcu_read_lock */ un = find_alloc_undo(ns, semid); if (IS_ERR(un)) { error = PTR_ERR(un); goto out_free; } - } else + } else { un = NULL; + rcu_read_lock(); + } - INIT_LIST_HEAD(&tasks); - - rcu_read_lock(); sma = sem_obtain_object_check(ns, semid); if (IS_ERR(sma)) { - if (un) - rcu_read_unlock(); + rcu_read_unlock(); error = PTR_ERR(sma); goto out_free; } @@ -1534,23 +1617,9 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, * "un" itself is guaranteed by rcu. */ error = -EIDRM; - ipc_lock_object(&sma->sem_perm); - if (un) { - if (un->semid == -1) { - rcu_read_unlock(); - goto out_unlock_free; - } else { - /* - * rcu lock can be released, "un" cannot disappear: - * - sem_lock is acquired, thus IPC_RMID is - * impossible. - * - exit_sem is impossible, it always operates on - * current (or a dead task). - */ - - rcu_read_unlock(); - } - } + locknum = sem_lock(sma, sops, nsops); + if (un && un->semid == -1) + goto out_unlock_free; error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current)); if (error <= 0) { @@ -1591,7 +1660,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, sleep_again: current->state = TASK_INTERRUPTIBLE; - sem_unlock(sma); + sem_unlock(sma, locknum); if (timeout) jiffies_left = schedule_timeout(jiffies_left); @@ -1613,7 +1682,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, goto out_free; } - sma = sem_obtain_lock(ns, semid); + sma = sem_obtain_lock(ns, semid, sops, nsops, &locknum); /* * Wait until it's guaranteed that no wakeup_sem_queue_do() is ongoing. @@ -1652,7 +1721,7 @@ SYSCALL_DEFINE4(semtimedop, int, semid, struct sembuf __user *, tsops, unlink_queue(sma, &queue); out_unlock_free: - sem_unlock(sma); + sem_unlock(sma, locknum); out_wakeup: wake_up_sem_queue_do(&tasks); out_free: @@ -1716,8 +1785,7 @@ void exit_sem(struct task_struct *tsk) struct sem_array *sma; struct sem_undo *un; struct list_head tasks; - int semid; - int i; + int semid, i; rcu_read_lock(); un = list_entry_rcu(ulp->list_proc.next, @@ -1726,23 +1794,26 @@ void exit_sem(struct task_struct *tsk) semid = -1; else semid = un->semid; - rcu_read_unlock(); - if (semid == -1) + if (semid == -1) { + rcu_read_unlock(); break; + } - sma = sem_lock_check(tsk->nsproxy->ipc_ns, un->semid); - + sma = sem_obtain_object_check(tsk->nsproxy->ipc_ns, un->semid); /* exit_sem raced with IPC_RMID, nothing to do */ - if (IS_ERR(sma)) + if (IS_ERR(sma)) { + rcu_read_unlock(); continue; + } + sem_lock(sma, NULL, -1); un = __lookup_undo(ulp, semid); if (un == NULL) { /* exit_sem raced with IPC_RMID+semget() that created * exactly the same semid. Nothing to do. */ - sem_unlock(sma); + sem_unlock(sma, -1); continue; } @@ -1782,7 +1853,7 @@ void exit_sem(struct task_struct *tsk) /* maybe some queued-up processes were waiting for this */ INIT_LIST_HEAD(&tasks); do_smart_update(sma, NULL, 0, 1, &tasks); - sem_unlock(sma); + sem_unlock(sma, -1); wake_up_sem_queue_do(&tasks); kfree_rcu(un, rcu);
CWE-189
null
null
23,663
void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out) { out->key = in->key; SET_UID(out->uid, in->uid); SET_GID(out->gid, in->gid); SET_UID(out->cuid, in->cuid); SET_GID(out->cgid, in->cgid); out->mode = in->mode; out->seq = in->seq; }
DoS
0
void ipc64_perm_to_ipc_perm (struct ipc64_perm *in, struct ipc_perm *out) { out->key = in->key; SET_UID(out->uid, in->uid); SET_GID(out->gid, in->gid); SET_UID(out->cuid, in->cuid); SET_GID(out->cgid, in->cgid); out->mode = in->mode; out->seq = in->seq; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,664
int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size) { kuid_t euid; kgid_t egid; int id; int next_id = ids->next_id; if (size > IPCMNI) size = IPCMNI; if (ids->in_use >= size) return -ENOSPC; idr_preload(GFP_KERNEL); spin_lock_init(&new->lock); new->deleted = 0; rcu_read_lock(); spin_lock(&new->lock); id = idr_alloc(&ids->ipcs_idr, new, (next_id < 0) ? 0 : ipcid_to_idx(next_id), 0, GFP_NOWAIT); idr_preload_end(); if (id < 0) { spin_unlock(&new->lock); rcu_read_unlock(); return id; } ids->in_use++; current_euid_egid(&euid, &egid); new->cuid = new->uid = euid; new->gid = new->cgid = egid; if (next_id < 0) { new->seq = ids->seq++; if (ids->seq > ids->seq_max) ids->seq = 0; } else { new->seq = ipcid_to_seqx(next_id); ids->next_id = -1; } new->id = ipc_buildid(id, new->seq); return id; }
DoS
0
int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size) { kuid_t euid; kgid_t egid; int id; int next_id = ids->next_id; if (size > IPCMNI) size = IPCMNI; if (ids->in_use >= size) return -ENOSPC; idr_preload(GFP_KERNEL); spin_lock_init(&new->lock); new->deleted = 0; rcu_read_lock(); spin_lock(&new->lock); id = idr_alloc(&ids->ipcs_idr, new, (next_id < 0) ? 0 : ipcid_to_idx(next_id), 0, GFP_NOWAIT); idr_preload_end(); if (id < 0) { spin_unlock(&new->lock); rcu_read_unlock(); return id; } ids->in_use++; current_euid_egid(&euid, &egid); new->cuid = new->uid = euid; new->gid = new->cgid = egid; if (next_id < 0) { new->seq = ids->seq++; if (ids->seq > ids->seq_max) ids->seq = 0; } else { new->seq = ipcid_to_seqx(next_id); ids->next_id = -1; } new->id = ipc_buildid(id, new->seq); return id; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,665
static int ipc_check_perms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, struct ipc_ops *ops, struct ipc_params *params) { int err; if (ipcperms(ns, ipcp, params->flg)) err = -EACCES; else { err = ops->associate(ipcp, params->flg); if (!err) err = ipcp->id; } return err; }
DoS
0
static int ipc_check_perms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, struct ipc_ops *ops, struct ipc_params *params) { int err; if (ipcperms(ns, ipcp, params->flg)) err = -EACCES; else { err = ops->associate(ipcp, params->flg); if (!err) err = ipcp->id; } return err; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,666
static void ipc_do_vfree(struct work_struct *work) { vfree(container_of(work, struct ipc_rcu_sched, work)); }
DoS
0
static void ipc_do_vfree(struct work_struct *work) { vfree(container_of(work, struct ipc_rcu_sched, work)); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,667
static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key) { struct kern_ipc_perm *ipc; int next_id; int total; for (total = 0, next_id = 0; total < ids->in_use; next_id++) { ipc = idr_find(&ids->ipcs_idr, next_id); if (ipc == NULL) continue; if (ipc->key != key) { total++; continue; } ipc_lock_by_ptr(ipc); return ipc; } return NULL; }
DoS
0
static struct kern_ipc_perm *ipc_findkey(struct ipc_ids *ids, key_t key) { struct kern_ipc_perm *ipc; int next_id; int total; for (total = 0, next_id = 0; total < ids->in_use; next_id++) { ipc = idr_find(&ids->ipcs_idr, next_id); if (ipc == NULL) continue; if (ipc->key != key) { total++; continue; } ipc_lock_by_ptr(ipc); return ipc; } return NULL; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,668
static int __init ipc_init(void) { sem_init(); msg_init(); shm_init(); register_hotmemory_notifier(&ipc_memory_nb); register_ipcns_notifier(&init_ipc_ns); return 0; }
DoS
0
static int __init ipc_init(void) { sem_init(); msg_init(); shm_init(); register_hotmemory_notifier(&ipc_memory_nb); register_ipcns_notifier(&init_ipc_ns); return 0; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,669
struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out; out = ipc_lock(ids, id); if (IS_ERR(out)) return out; if (ipc_checkid(out, id)) { ipc_unlock(out); return ERR_PTR(-EIDRM); } return out; }
DoS
0
struct kern_ipc_perm *ipc_lock_check(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out; out = ipc_lock(ids, id); if (IS_ERR(out)) return out; if (ipc_checkid(out, id)) { ipc_unlock(out); return ERR_PTR(-EIDRM); } return out; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,670
static int ipc_memory_callback(struct notifier_block *self, unsigned long action, void *arg) { static DECLARE_WORK(ipc_memory_wq, ipc_memory_notifier); switch (action) { case MEM_ONLINE: /* memory successfully brought online */ case MEM_OFFLINE: /* or offline: it's time to recompute msgmni */ /* * This is done by invoking the ipcns notifier chain with the * IPC_MEMCHANGED event. * In order not to keep the lock on the hotplug memory chain * for too long, queue a work item that will, when waken up, * activate the ipcns notification chain. * No need to keep several ipc work items on the queue. */ if (!work_pending(&ipc_memory_wq)) schedule_work(&ipc_memory_wq); break; case MEM_GOING_ONLINE: case MEM_GOING_OFFLINE: case MEM_CANCEL_ONLINE: case MEM_CANCEL_OFFLINE: default: break; } return NOTIFY_OK; }
DoS
0
static int ipc_memory_callback(struct notifier_block *self, unsigned long action, void *arg) { static DECLARE_WORK(ipc_memory_wq, ipc_memory_notifier); switch (action) { case MEM_ONLINE: /* memory successfully brought online */ case MEM_OFFLINE: /* or offline: it's time to recompute msgmni */ /* * This is done by invoking the ipcns notifier chain with the * IPC_MEMCHANGED event. * In order not to keep the lock on the hotplug memory chain * for too long, queue a work item that will, when waken up, * activate the ipcns notification chain. * No need to keep several ipc work items on the queue. */ if (!work_pending(&ipc_memory_wq)) schedule_work(&ipc_memory_wq); break; case MEM_GOING_ONLINE: case MEM_GOING_OFFLINE: case MEM_CANCEL_ONLINE: case MEM_CANCEL_OFFLINE: default: break; } return NOTIFY_OK; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,671
static void ipc_memory_notifier(struct work_struct *work) { ipcns_notify(IPCNS_MEMCHANGED); }
DoS
0
static void ipc_memory_notifier(struct work_struct *work) { ipcns_notify(IPCNS_MEMCHANGED); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,672
struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out; int lid = ipcid_to_idx(id); out = idr_find(&ids->ipcs_idr, lid); if (!out) return ERR_PTR(-EINVAL); return out; }
DoS
0
struct kern_ipc_perm *ipc_obtain_object(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out; int lid = ipcid_to_idx(id); out = idr_find(&ids->ipcs_idr, lid); if (!out) return ERR_PTR(-EINVAL); return out; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,673
struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out = ipc_obtain_object(ids, id); if (IS_ERR(out)) goto out; if (ipc_checkid(out, id)) return ERR_PTR(-EIDRM); out: return out; }
DoS
0
struct kern_ipc_perm *ipc_obtain_object_check(struct ipc_ids *ids, int id) { struct kern_ipc_perm *out = ipc_obtain_object(ids, id); if (IS_ERR(out)) goto out; if (ipc_checkid(out, id)) return ERR_PTR(-EIDRM); out: return out; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,674
void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) { int lid = ipcid_to_idx(ipcp->id); idr_remove(&ids->ipcs_idr, lid); ids->in_use--; ipcp->deleted = 1; return; }
DoS
0
void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) { int lid = ipcid_to_idx(ipcp->id); idr_remove(&ids->ipcs_idr, lid); ids->in_use--; ipcp->deleted = 1; return; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,675
static void ipc_schedule_free(struct rcu_head *head) { struct ipc_rcu_grace *grace; struct ipc_rcu_sched *sched; grace = container_of(head, struct ipc_rcu_grace, rcu); sched = container_of(&(grace->data[0]), struct ipc_rcu_sched, data[0]); INIT_WORK(&sched->work, ipc_do_vfree); schedule_work(&sched->work); }
DoS
0
static void ipc_schedule_free(struct rcu_head *head) { struct ipc_rcu_grace *grace; struct ipc_rcu_sched *sched; grace = container_of(head, struct ipc_rcu_grace, rcu); sched = container_of(&(grace->data[0]), struct ipc_rcu_sched, data[0]); INIT_WORK(&sched->work, ipc_do_vfree); schedule_work(&sched->work); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,676
int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out) { kuid_t uid = make_kuid(current_user_ns(), in->uid); kgid_t gid = make_kgid(current_user_ns(), in->gid); if (!uid_valid(uid) || !gid_valid(gid)) return -EINVAL; out->uid = uid; out->gid = gid; out->mode = (out->mode & ~S_IRWXUGO) | (in->mode & S_IRWXUGO); return 0; }
DoS
0
int ipc_update_perm(struct ipc64_perm *in, struct kern_ipc_perm *out) { kuid_t uid = make_kuid(current_user_ns(), in->uid); kgid_t gid = make_kgid(current_user_ns(), in->gid); if (!uid_valid(uid) || !gid_valid(gid)) return -EINVAL; out->uid = uid; out->gid = gid; out->mode = (out->mode & ~S_IRWXUGO) | (in->mode & S_IRWXUGO); return 0; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,677
struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns, struct ipc_ids *ids, int id, int cmd, struct ipc64_perm *perm, int extra_perm) { struct kern_ipc_perm *ipcp; ipcp = ipcctl_pre_down_nolock(ns, ids, id, cmd, perm, extra_perm); if (IS_ERR(ipcp)) goto out; spin_lock(&ipcp->lock); out: return ipcp; }
DoS
0
struct kern_ipc_perm *ipcctl_pre_down(struct ipc_namespace *ns, struct ipc_ids *ids, int id, int cmd, struct ipc64_perm *perm, int extra_perm) { struct kern_ipc_perm *ipcp; ipcp = ipcctl_pre_down_nolock(ns, ids, id, cmd, perm, extra_perm); if (IS_ERR(ipcp)) goto out; spin_lock(&ipcp->lock); out: return ipcp; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,678
struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns, struct ipc_ids *ids, int id, int cmd, struct ipc64_perm *perm, int extra_perm) { kuid_t euid; int err = -EPERM; struct kern_ipc_perm *ipcp; down_write(&ids->rw_mutex); rcu_read_lock(); ipcp = ipc_obtain_object_check(ids, id); if (IS_ERR(ipcp)) { err = PTR_ERR(ipcp); goto out_up; } audit_ipc_obj(ipcp); if (cmd == IPC_SET) audit_ipc_set_perm(extra_perm, perm->uid, perm->gid, perm->mode); euid = current_euid(); if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid) || ns_capable(ns->user_ns, CAP_SYS_ADMIN)) return ipcp; out_up: /* * Unsuccessful lookup, unlock and return * the corresponding error. */ rcu_read_unlock(); up_write(&ids->rw_mutex); return ERR_PTR(err); }
DoS
0
struct kern_ipc_perm *ipcctl_pre_down_nolock(struct ipc_namespace *ns, struct ipc_ids *ids, int id, int cmd, struct ipc64_perm *perm, int extra_perm) { kuid_t euid; int err = -EPERM; struct kern_ipc_perm *ipcp; down_write(&ids->rw_mutex); rcu_read_lock(); ipcp = ipc_obtain_object_check(ids, id); if (IS_ERR(ipcp)) { err = PTR_ERR(ipcp); goto out_up; } audit_ipc_obj(ipcp); if (cmd == IPC_SET) audit_ipc_set_perm(extra_perm, perm->uid, perm->gid, perm->mode); euid = current_euid(); if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid) || ns_capable(ns->user_ns, CAP_SYS_ADMIN)) return ipcp; out_up: /* * Unsuccessful lookup, unlock and return * the corresponding error. */ rcu_read_unlock(); up_write(&ids->rw_mutex); return ERR_PTR(err); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,679
int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids, struct ipc_ops *ops, struct ipc_params *params) { if (params->key == IPC_PRIVATE) return ipcget_new(ns, ids, ops, params); else return ipcget_public(ns, ids, ops, params); }
DoS
0
int ipcget(struct ipc_namespace *ns, struct ipc_ids *ids, struct ipc_ops *ops, struct ipc_params *params) { if (params->key == IPC_PRIVATE) return ipcget_new(ns, ids, ops, params); else return ipcget_public(ns, ids, ops, params); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,680
static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids, struct ipc_ops *ops, struct ipc_params *params) { int err; down_write(&ids->rw_mutex); err = ops->getnew(ns, params); up_write(&ids->rw_mutex); return err; }
DoS
0
static int ipcget_new(struct ipc_namespace *ns, struct ipc_ids *ids, struct ipc_ops *ops, struct ipc_params *params) { int err; down_write(&ids->rw_mutex); err = ops->getnew(ns, params); up_write(&ids->rw_mutex); return err; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,681
static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids, struct ipc_ops *ops, struct ipc_params *params) { struct kern_ipc_perm *ipcp; int flg = params->flg; int err; /* * Take the lock as a writer since we are potentially going to add * a new entry + read locks are not "upgradable" */ down_write(&ids->rw_mutex); ipcp = ipc_findkey(ids, params->key); if (ipcp == NULL) { /* key not used */ if (!(flg & IPC_CREAT)) err = -ENOENT; else err = ops->getnew(ns, params); } else { /* ipc object has been locked by ipc_findkey() */ if (flg & IPC_CREAT && flg & IPC_EXCL) err = -EEXIST; else { err = 0; if (ops->more_checks) err = ops->more_checks(ipcp, params); if (!err) /* * ipc_check_perms returns the IPC id on * success */ err = ipc_check_perms(ns, ipcp, ops, params); } ipc_unlock(ipcp); } up_write(&ids->rw_mutex); return err; }
DoS
0
static int ipcget_public(struct ipc_namespace *ns, struct ipc_ids *ids, struct ipc_ops *ops, struct ipc_params *params) { struct kern_ipc_perm *ipcp; int flg = params->flg; int err; /* * Take the lock as a writer since we are potentially going to add * a new entry + read locks are not "upgradable" */ down_write(&ids->rw_mutex); ipcp = ipc_findkey(ids, params->key); if (ipcp == NULL) { /* key not used */ if (!(flg & IPC_CREAT)) err = -ENOENT; else err = ops->getnew(ns, params); } else { /* ipc object has been locked by ipc_findkey() */ if (flg & IPC_CREAT && flg & IPC_EXCL) err = -EEXIST; else { err = 0; if (ops->more_checks) err = ops->more_checks(ipcp, params); if (!err) /* * ipc_check_perms returns the IPC id on * success */ err = ipc_check_perms(ns, ipcp, ops, params); } ipc_unlock(ipcp); } up_write(&ids->rw_mutex); return err; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,682
int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag) { kuid_t euid = current_euid(); int requested_mode, granted_mode; audit_ipc_obj(ipcp); requested_mode = (flag >> 6) | (flag >> 3) | flag; granted_mode = ipcp->mode; if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid)) granted_mode >>= 6; else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid)) granted_mode >>= 3; /* is there some bit set in requested_mode but not in granted_mode? */ if ((requested_mode & ~granted_mode & 0007) && !ns_capable(ns->user_ns, CAP_IPC_OWNER)) return -1; return security_ipc_permission(ipcp, flag); }
DoS
0
int ipcperms(struct ipc_namespace *ns, struct kern_ipc_perm *ipcp, short flag) { kuid_t euid = current_euid(); int requested_mode, granted_mode; audit_ipc_obj(ipcp); requested_mode = (flag >> 6) | (flag >> 3) | flag; granted_mode = ipcp->mode; if (uid_eq(euid, ipcp->cuid) || uid_eq(euid, ipcp->uid)) granted_mode >>= 6; else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid)) granted_mode >>= 3; /* is there some bit set in requested_mode but not in granted_mode? */ if ((requested_mode & ~granted_mode & 0007) && !ns_capable(ns->user_ns, CAP_IPC_OWNER)) return -1; return security_ipc_permission(ipcp, flag); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,683
void kernel_to_ipc64_perm (struct kern_ipc_perm *in, struct ipc64_perm *out) { out->key = in->key; out->uid = from_kuid_munged(current_user_ns(), in->uid); out->gid = from_kgid_munged(current_user_ns(), in->gid); out->cuid = from_kuid_munged(current_user_ns(), in->cuid); out->cgid = from_kgid_munged(current_user_ns(), in->cgid); out->mode = in->mode; out->seq = in->seq; }
DoS
0
void kernel_to_ipc64_perm (struct kern_ipc_perm *in, struct ipc64_perm *out) { out->key = in->key; out->uid = from_kuid_munged(current_user_ns(), in->uid); out->gid = from_kgid_munged(current_user_ns(), in->gid); out->cuid = from_kuid_munged(current_user_ns(), in->cuid); out->cgid = from_kgid_munged(current_user_ns(), in->cgid); out->mode = in->mode; out->seq = in->seq; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,684
static inline int rcu_use_vmalloc(int size) { /* Too big for a single page? */ if (HDRLEN_KMALLOC + size > PAGE_SIZE) return 1; return 0; }
DoS
0
static inline int rcu_use_vmalloc(int size) { /* Too big for a single page? */ if (HDRLEN_KMALLOC + size > PAGE_SIZE) return 1; return 0; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,685
static int sysvipc_proc_open(struct inode *inode, struct file *file) { int ret; struct seq_file *seq; struct ipc_proc_iter *iter; ret = -ENOMEM; iter = kmalloc(sizeof(*iter), GFP_KERNEL); if (!iter) goto out; ret = seq_open(file, &sysvipc_proc_seqops); if (ret) goto out_kfree; seq = file->private_data; seq->private = iter; iter->iface = PDE(inode)->data; iter->ns = get_ipc_ns(current->nsproxy->ipc_ns); out: return ret; out_kfree: kfree(iter); goto out; }
DoS
0
static int sysvipc_proc_open(struct inode *inode, struct file *file) { int ret; struct seq_file *seq; struct ipc_proc_iter *iter; ret = -ENOMEM; iter = kmalloc(sizeof(*iter), GFP_KERNEL); if (!iter) goto out; ret = seq_open(file, &sysvipc_proc_seqops); if (ret) goto out_kfree; seq = file->private_data; seq->private = iter; iter->iface = PDE(inode)->data; iter->ns = get_ipc_ns(current->nsproxy->ipc_ns); out: return ret; out_kfree: kfree(iter); goto out; }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,686
static int sysvipc_proc_release(struct inode *inode, struct file *file) { struct seq_file *seq = file->private_data; struct ipc_proc_iter *iter = seq->private; put_ipc_ns(iter->ns); return seq_release_private(inode, file); }
DoS
0
static int sysvipc_proc_release(struct inode *inode, struct file *file) { struct seq_file *seq = file->private_data; struct ipc_proc_iter *iter = seq->private; put_ipc_ns(iter->ns); return seq_release_private(inode, file); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,687
static int sysvipc_proc_show(struct seq_file *s, void *it) { struct ipc_proc_iter *iter = s->private; struct ipc_proc_iface *iface = iter->iface; if (it == SEQ_START_TOKEN) return seq_puts(s, iface->header); return iface->show(s, it); }
DoS
0
static int sysvipc_proc_show(struct seq_file *s, void *it) { struct ipc_proc_iter *iter = s->private; struct ipc_proc_iface *iface = iter->iface; if (it == SEQ_START_TOKEN) return seq_puts(s, iface->header); return iface->show(s, it); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,688
static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) { struct ipc_proc_iter *iter = s->private; struct ipc_proc_iface *iface = iter->iface; struct ipc_ids *ids; ids = &iter->ns->ids[iface->ids]; /* * Take the lock - this will be released by the corresponding * call to stop(). */ down_read(&ids->rw_mutex); /* pos < 0 is invalid */ if (*pos < 0) return NULL; /* pos == 0 means header */ if (*pos == 0) return SEQ_START_TOKEN; /* Find the (pos-1)th ipc */ return sysvipc_find_ipc(ids, *pos - 1, pos); }
DoS
0
static void *sysvipc_proc_start(struct seq_file *s, loff_t *pos) { struct ipc_proc_iter *iter = s->private; struct ipc_proc_iface *iface = iter->iface; struct ipc_ids *ids; ids = &iter->ns->ids[iface->ids]; /* * Take the lock - this will be released by the corresponding * call to stop(). */ down_read(&ids->rw_mutex); /* pos < 0 is invalid */ if (*pos < 0) return NULL; /* pos == 0 means header */ if (*pos == 0) return SEQ_START_TOKEN; /* Find the (pos-1)th ipc */ return sysvipc_find_ipc(ids, *pos - 1, pos); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,689
static void sysvipc_proc_stop(struct seq_file *s, void *it) { struct kern_ipc_perm *ipc = it; struct ipc_proc_iter *iter = s->private; struct ipc_proc_iface *iface = iter->iface; struct ipc_ids *ids; /* If we had a locked structure, release it */ if (ipc && ipc != SEQ_START_TOKEN) ipc_unlock(ipc); ids = &iter->ns->ids[iface->ids]; /* Release the lock we took in start() */ up_read(&ids->rw_mutex); }
DoS
0
static void sysvipc_proc_stop(struct seq_file *s, void *it) { struct kern_ipc_perm *ipc = it; struct ipc_proc_iter *iter = s->private; struct ipc_proc_iface *iface = iter->iface; struct ipc_ids *ids; /* If we had a locked structure, release it */ if (ipc && ipc != SEQ_START_TOKEN) ipc_unlock(ipc); ids = &iter->ns->ids[iface->ids]; /* Release the lock we took in start() */ up_read(&ids->rw_mutex); }
@@ -439,9 +439,9 @@ void ipc_rmid(struct ipc_ids *ids, struct kern_ipc_perm *ipcp) * NULL is returned if the allocation fails */ -void* ipc_alloc(int size) +void *ipc_alloc(int size) { - void* out; + void *out; if(size > PAGE_SIZE) out = vmalloc(size); else @@ -478,7 +478,7 @@ void ipc_free(void* ptr, int size) */ struct ipc_rcu_hdr { - int refcount; + atomic_t refcount; int is_vmalloc; void *data[0]; }; @@ -516,39 +516,41 @@ static inline int rcu_use_vmalloc(int size) * @size: size desired * * Allocate memory for the rcu header structure + the object. - * Returns the pointer to the object. - * NULL is returned if the allocation fails. + * Returns the pointer to the object or NULL upon failure. */ - -void* ipc_rcu_alloc(int size) +void *ipc_rcu_alloc(int size) { - void* out; - /* + void *out; + + /* * We prepend the allocation with the rcu struct, and - * workqueue if necessary (for vmalloc). + * workqueue if necessary (for vmalloc). */ if (rcu_use_vmalloc(size)) { out = vmalloc(HDRLEN_VMALLOC + size); - if (out) { - out += HDRLEN_VMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_VMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 1; } else { out = kmalloc(HDRLEN_KMALLOC + size, GFP_KERNEL); - if (out) { - out += HDRLEN_KMALLOC; - container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; - container_of(out, struct ipc_rcu_hdr, data)->refcount = 1; - } + if (!out) + goto done; + + out += HDRLEN_KMALLOC; + container_of(out, struct ipc_rcu_hdr, data)->is_vmalloc = 0; } + /* set reference counter no matter what kind of allocation was done */ + atomic_set(&container_of(out, struct ipc_rcu_hdr, data)->refcount, 1); +done: return out; } -void ipc_rcu_getref(void *ptr) +int ipc_rcu_getref(void *ptr) { - container_of(ptr, struct ipc_rcu_hdr, data)->refcount++; + return atomic_inc_not_zero(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount); } static void ipc_do_vfree(struct work_struct *work) @@ -578,7 +580,7 @@ static void ipc_schedule_free(struct rcu_head *head) void ipc_rcu_putref(void *ptr) { - if (--container_of(ptr, struct ipc_rcu_hdr, data)->refcount > 0) + if (!atomic_dec_and_test(&container_of(ptr, struct ipc_rcu_hdr, data)->refcount)) return; if (container_of(ptr, struct ipc_rcu_hdr, data)->is_vmalloc) {
CWE-189
null
null
23,690
static int __ip_append_data(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork, struct page_frag *pfrag, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; struct ip_options *opt = cork->opt; int hh_len; int exthdrlen; int mtu; int copy; int err; int offset = 0; unsigned int maxfraglen, fragheaderlen; int csummode = CHECKSUM_NONE; struct rtable *rt = (struct rtable *)cork->dst; skb = skb_peek_tail(queue); exthdrlen = !skb ? rt->dst.header_len : 0; mtu = cork->fragsize; hh_len = LL_RESERVED_SPACE(rt->dst.dev); fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; if (cork->length + length > 0xFFFF - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu-exthdrlen); return -EMSGSIZE; } /* * transhdrlen > 0 means that this is the first fragment and we wish * it won't be fragmented in the future. */ if (transhdrlen && length + fragheaderlen <= mtu && rt->dst.dev->features & NETIF_F_V4_CSUM && !exthdrlen) csummode = CHECKSUM_PARTIAL; cork->length += length; if (((length > mtu) || (skb && skb_is_gso(skb))) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len) { err = ip_ufo_append_data(sk, queue, getfrag, from, length, hh_len, fragheaderlen, transhdrlen, maxfraglen, flags); if (err) goto error; return 0; } /* So, what's going on in the loop below? * * We use calculated fragment length to generate chained skb, * each of segments is IP fragment ready for sending to network after * adding appropriate IP header. */ if (!skb) goto alloc_new_skb; while (length > 0) { /* Check if the remaining data fits into current packet. */ copy = mtu - skb->len; if (copy < length) copy = maxfraglen - skb->len; if (copy <= 0) { char *data; unsigned int datalen; unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; struct sk_buff *skb_prev; alloc_new_skb: skb_prev = skb; if (skb_prev) fraggap = skb_prev->len - maxfraglen; else fraggap = 0; /* * If remaining data exceeds the mtu, * we know we need more fragment(s). */ datalen = length + fraggap; if (datalen > mtu - fragheaderlen) datalen = maxfraglen - fragheaderlen; fraglen = datalen + fragheaderlen; if ((flags & MSG_MORE) && !(rt->dst.dev->features&NETIF_F_SG)) alloclen = mtu; else alloclen = fraglen; alloclen += exthdrlen; /* The last fragment gets additional space at tail. * Note, with MSG_MORE we overallocate on fragments, * because we have no idea what fragment will be * the last. */ if (datalen == length + fraggap) alloclen += rt->dst.trailer_len; if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len + 15, (flags & MSG_DONTWAIT), &err); } else { skb = NULL; if (atomic_read(&sk->sk_wmem_alloc) <= 2 * sk->sk_sndbuf) skb = sock_wmalloc(sk, alloclen + hh_len + 15, 1, sk->sk_allocation); if (unlikely(skb == NULL)) err = -ENOBUFS; else /* only the initial fragment is time stamped */ cork->tx_flags = 0; } if (skb == NULL) goto error; /* * Fill in the control structures */ skb->ip_summed = csummode; skb->csum = 0; skb_reserve(skb, hh_len); skb_shinfo(skb)->tx_flags = cork->tx_flags; /* * Find where to start putting bytes. */ data = skb_put(skb, fraglen + exthdrlen); skb_set_network_header(skb, exthdrlen); skb->transport_header = (skb->network_header + fragheaderlen); data += fragheaderlen + exthdrlen; if (fraggap) { skb->csum = skb_copy_and_csum_bits( skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; } offset += copy; length -= datalen - fraggap; transhdrlen = 0; exthdrlen = 0; csummode = CHECKSUM_NONE; /* * Put the packet on the pending queue. */ __skb_queue_tail(queue, skb); continue; } if (copy > length) copy = length; if (!(rt->dst.dev->features&NETIF_F_SG)) { unsigned int off; off = skb->len; if (getfrag(from, skb_put(skb, copy), offset, copy, off, skb) < 0) { __skb_trim(skb, off); err = -EFAULT; goto error; } } else { int i = skb_shinfo(skb)->nr_frags; err = -ENOMEM; if (!sk_page_frag_refill(sk, pfrag)) goto error; if (!skb_can_coalesce(skb, i, pfrag->page, pfrag->offset)) { err = -EMSGSIZE; if (i == MAX_SKB_FRAGS) goto error; __skb_fill_page_desc(skb, i, pfrag->page, pfrag->offset, 0); skb_shinfo(skb)->nr_frags = ++i; get_page(pfrag->page); } copy = min_t(int, copy, pfrag->size - pfrag->offset); if (getfrag(from, page_address(pfrag->page) + pfrag->offset, offset, copy, skb->len, skb) < 0) goto error_efault; pfrag->offset += copy; skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); skb->len += copy; skb->data_len += copy; skb->truesize += copy; atomic_add(copy, &sk->sk_wmem_alloc); } offset += copy; length -= copy; } return 0; error_efault: err = -EFAULT; error: cork->length -= length; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); return err; }
DoS +Priv Mem. Corr.
0
static int __ip_append_data(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork, struct page_frag *pfrag, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, unsigned int flags) { struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; struct ip_options *opt = cork->opt; int hh_len; int exthdrlen; int mtu; int copy; int err; int offset = 0; unsigned int maxfraglen, fragheaderlen; int csummode = CHECKSUM_NONE; struct rtable *rt = (struct rtable *)cork->dst; skb = skb_peek_tail(queue); exthdrlen = !skb ? rt->dst.header_len : 0; mtu = cork->fragsize; hh_len = LL_RESERVED_SPACE(rt->dst.dev); fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; if (cork->length + length > 0xFFFF - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu-exthdrlen); return -EMSGSIZE; } /* * transhdrlen > 0 means that this is the first fragment and we wish * it won't be fragmented in the future. */ if (transhdrlen && length + fragheaderlen <= mtu && rt->dst.dev->features & NETIF_F_V4_CSUM && !exthdrlen) csummode = CHECKSUM_PARTIAL; cork->length += length; if (((length > mtu) || (skb && skb_is_gso(skb))) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO) && !rt->dst.header_len) { err = ip_ufo_append_data(sk, queue, getfrag, from, length, hh_len, fragheaderlen, transhdrlen, maxfraglen, flags); if (err) goto error; return 0; } /* So, what's going on in the loop below? * * We use calculated fragment length to generate chained skb, * each of segments is IP fragment ready for sending to network after * adding appropriate IP header. */ if (!skb) goto alloc_new_skb; while (length > 0) { /* Check if the remaining data fits into current packet. */ copy = mtu - skb->len; if (copy < length) copy = maxfraglen - skb->len; if (copy <= 0) { char *data; unsigned int datalen; unsigned int fraglen; unsigned int fraggap; unsigned int alloclen; struct sk_buff *skb_prev; alloc_new_skb: skb_prev = skb; if (skb_prev) fraggap = skb_prev->len - maxfraglen; else fraggap = 0; /* * If remaining data exceeds the mtu, * we know we need more fragment(s). */ datalen = length + fraggap; if (datalen > mtu - fragheaderlen) datalen = maxfraglen - fragheaderlen; fraglen = datalen + fragheaderlen; if ((flags & MSG_MORE) && !(rt->dst.dev->features&NETIF_F_SG)) alloclen = mtu; else alloclen = fraglen; alloclen += exthdrlen; /* The last fragment gets additional space at tail. * Note, with MSG_MORE we overallocate on fragments, * because we have no idea what fragment will be * the last. */ if (datalen == length + fraggap) alloclen += rt->dst.trailer_len; if (transhdrlen) { skb = sock_alloc_send_skb(sk, alloclen + hh_len + 15, (flags & MSG_DONTWAIT), &err); } else { skb = NULL; if (atomic_read(&sk->sk_wmem_alloc) <= 2 * sk->sk_sndbuf) skb = sock_wmalloc(sk, alloclen + hh_len + 15, 1, sk->sk_allocation); if (unlikely(skb == NULL)) err = -ENOBUFS; else /* only the initial fragment is time stamped */ cork->tx_flags = 0; } if (skb == NULL) goto error; /* * Fill in the control structures */ skb->ip_summed = csummode; skb->csum = 0; skb_reserve(skb, hh_len); skb_shinfo(skb)->tx_flags = cork->tx_flags; /* * Find where to start putting bytes. */ data = skb_put(skb, fraglen + exthdrlen); skb_set_network_header(skb, exthdrlen); skb->transport_header = (skb->network_header + fragheaderlen); data += fragheaderlen + exthdrlen; if (fraggap) { skb->csum = skb_copy_and_csum_bits( skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); data += fraggap; pskb_trim_unique(skb_prev, maxfraglen); } copy = datalen - transhdrlen - fraggap; if (copy > 0 && getfrag(from, data + transhdrlen, offset, copy, fraggap, skb) < 0) { err = -EFAULT; kfree_skb(skb); goto error; } offset += copy; length -= datalen - fraggap; transhdrlen = 0; exthdrlen = 0; csummode = CHECKSUM_NONE; /* * Put the packet on the pending queue. */ __skb_queue_tail(queue, skb); continue; } if (copy > length) copy = length; if (!(rt->dst.dev->features&NETIF_F_SG)) { unsigned int off; off = skb->len; if (getfrag(from, skb_put(skb, copy), offset, copy, off, skb) < 0) { __skb_trim(skb, off); err = -EFAULT; goto error; } } else { int i = skb_shinfo(skb)->nr_frags; err = -ENOMEM; if (!sk_page_frag_refill(sk, pfrag)) goto error; if (!skb_can_coalesce(skb, i, pfrag->page, pfrag->offset)) { err = -EMSGSIZE; if (i == MAX_SKB_FRAGS) goto error; __skb_fill_page_desc(skb, i, pfrag->page, pfrag->offset, 0); skb_shinfo(skb)->nr_frags = ++i; get_page(pfrag->page); } copy = min_t(int, copy, pfrag->size - pfrag->offset); if (getfrag(from, page_address(pfrag->page) + pfrag->offset, offset, copy, skb->len, skb) < 0) goto error_efault; pfrag->offset += copy; skb_frag_size_add(&skb_shinfo(skb)->frags[i - 1], copy); skb->len += copy; skb->data_len += copy; skb->truesize += copy; atomic_add(copy, &sk->sk_wmem_alloc); } offset += copy; length -= copy; } return 0; error_efault: err = -EFAULT; error: cork->length -= length; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); return err; }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,691
struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork) { struct sk_buff *skb, *tmp_skb; struct sk_buff **tail_skb; struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); struct ip_options *opt = NULL; struct rtable *rt = (struct rtable *)cork->dst; struct iphdr *iph; __be16 df = 0; __u8 ttl; if ((skb = __skb_dequeue(queue)) == NULL) goto out; tail_skb = &(skb_shinfo(skb)->frag_list); /* move skb->data to ip header from ext header */ if (skb->data < skb_network_header(skb)) __skb_pull(skb, skb_network_offset(skb)); while ((tmp_skb = __skb_dequeue(queue)) != NULL) { __skb_pull(tmp_skb, skb_network_header_len(skb)); *tail_skb = tmp_skb; tail_skb = &(tmp_skb->next); skb->len += tmp_skb->len; skb->data_len += tmp_skb->len; skb->truesize += tmp_skb->truesize; tmp_skb->destructor = NULL; tmp_skb->sk = NULL; } /* Unless user demanded real pmtu discovery (IP_PMTUDISC_DO), we allow * to fragment the frame generated here. No matter, what transforms * how transforms change size of the packet, it will come out. */ if (inet->pmtudisc < IP_PMTUDISC_DO) skb->local_df = 1; /* DF bit is set when we want to see DF on outgoing frames. * If local_df is set too, we still allow to fragment this frame * locally. */ if (inet->pmtudisc >= IP_PMTUDISC_DO || (skb->len <= dst_mtu(&rt->dst) && ip_dont_fragment(sk, &rt->dst))) df = htons(IP_DF); if (cork->flags & IPCORK_OPT) opt = cork->opt; if (rt->rt_type == RTN_MULTICAST) ttl = inet->mc_ttl; else ttl = ip_select_ttl(inet, &rt->dst); iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; iph->tos = inet->tos; iph->frag_off = df; iph->ttl = ttl; iph->protocol = sk->sk_protocol; ip_copy_addrs(iph, fl4); ip_select_ident(skb, &rt->dst, sk); if (opt) { iph->ihl += opt->optlen>>2; ip_options_build(skb, opt, cork->addr, rt, 0); } skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; /* * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec * on dst refcount */ cork->dst = NULL; skb_dst_set(skb, &rt->dst); if (iph->protocol == IPPROTO_ICMP) icmp_out_count(net, ((struct icmphdr *) skb_transport_header(skb))->type); ip_cork_release(cork); out: return skb; }
DoS +Priv Mem. Corr.
0
struct sk_buff *__ip_make_skb(struct sock *sk, struct flowi4 *fl4, struct sk_buff_head *queue, struct inet_cork *cork) { struct sk_buff *skb, *tmp_skb; struct sk_buff **tail_skb; struct inet_sock *inet = inet_sk(sk); struct net *net = sock_net(sk); struct ip_options *opt = NULL; struct rtable *rt = (struct rtable *)cork->dst; struct iphdr *iph; __be16 df = 0; __u8 ttl; if ((skb = __skb_dequeue(queue)) == NULL) goto out; tail_skb = &(skb_shinfo(skb)->frag_list); /* move skb->data to ip header from ext header */ if (skb->data < skb_network_header(skb)) __skb_pull(skb, skb_network_offset(skb)); while ((tmp_skb = __skb_dequeue(queue)) != NULL) { __skb_pull(tmp_skb, skb_network_header_len(skb)); *tail_skb = tmp_skb; tail_skb = &(tmp_skb->next); skb->len += tmp_skb->len; skb->data_len += tmp_skb->len; skb->truesize += tmp_skb->truesize; tmp_skb->destructor = NULL; tmp_skb->sk = NULL; } /* Unless user demanded real pmtu discovery (IP_PMTUDISC_DO), we allow * to fragment the frame generated here. No matter, what transforms * how transforms change size of the packet, it will come out. */ if (inet->pmtudisc < IP_PMTUDISC_DO) skb->local_df = 1; /* DF bit is set when we want to see DF on outgoing frames. * If local_df is set too, we still allow to fragment this frame * locally. */ if (inet->pmtudisc >= IP_PMTUDISC_DO || (skb->len <= dst_mtu(&rt->dst) && ip_dont_fragment(sk, &rt->dst))) df = htons(IP_DF); if (cork->flags & IPCORK_OPT) opt = cork->opt; if (rt->rt_type == RTN_MULTICAST) ttl = inet->mc_ttl; else ttl = ip_select_ttl(inet, &rt->dst); iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; iph->tos = inet->tos; iph->frag_off = df; iph->ttl = ttl; iph->protocol = sk->sk_protocol; ip_copy_addrs(iph, fl4); ip_select_ident(skb, &rt->dst, sk); if (opt) { iph->ihl += opt->optlen>>2; ip_options_build(skb, opt, cork->addr, rt, 0); } skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; /* * Steal rt from cork.dst to avoid a pair of atomic_inc/atomic_dec * on dst refcount */ cork->dst = NULL; skb_dst_set(skb, &rt->dst); if (iph->protocol == IPPROTO_ICMP) icmp_out_count(net, ((struct icmphdr *) skb_transport_header(skb))->type); ip_cork_release(cork); out: return skb; }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,692
ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, int offset, size_t size, int flags) { struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; struct rtable *rt; struct ip_options *opt = NULL; struct inet_cork *cork; int hh_len; int mtu; int len; int err; unsigned int maxfraglen, fragheaderlen, fraggap; if (inet->hdrincl) return -EPERM; if (flags&MSG_PROBE) return 0; if (skb_queue_empty(&sk->sk_write_queue)) return -EINVAL; cork = &inet->cork.base; rt = (struct rtable *)cork->dst; if (cork->flags & IPCORK_OPT) opt = cork->opt; if (!(rt->dst.dev->features&NETIF_F_SG)) return -EOPNOTSUPP; hh_len = LL_RESERVED_SPACE(rt->dst.dev); mtu = cork->fragsize; fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; if (cork->length + size > 0xFFFF - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu); return -EMSGSIZE; } if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) return -EINVAL; cork->length += size; if ((size + skb->len > mtu) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO)) { skb_shinfo(skb)->gso_size = mtu - fragheaderlen; skb_shinfo(skb)->gso_type = SKB_GSO_UDP; } while (size > 0) { int i; if (skb_is_gso(skb)) len = size; else { /* Check if the remaining data fits into current packet. */ len = mtu - skb->len; if (len < size) len = maxfraglen - skb->len; } if (len <= 0) { struct sk_buff *skb_prev; int alloclen; skb_prev = skb; fraggap = skb_prev->len - maxfraglen; alloclen = fragheaderlen + hh_len + fraggap + 15; skb = sock_wmalloc(sk, alloclen, 1, sk->sk_allocation); if (unlikely(!skb)) { err = -ENOBUFS; goto error; } /* * Fill in the control structures */ skb->ip_summed = CHECKSUM_NONE; skb->csum = 0; skb_reserve(skb, hh_len); /* * Find where to start putting bytes. */ skb_put(skb, fragheaderlen + fraggap); skb_reset_network_header(skb); skb->transport_header = (skb->network_header + fragheaderlen); if (fraggap) { skb->csum = skb_copy_and_csum_bits(skb_prev, maxfraglen, skb_transport_header(skb), fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); pskb_trim_unique(skb_prev, maxfraglen); } /* * Put the packet on the pending queue. */ __skb_queue_tail(&sk->sk_write_queue, skb); continue; } i = skb_shinfo(skb)->nr_frags; if (len > size) len = size; if (skb_can_coalesce(skb, i, page, offset)) { skb_frag_size_add(&skb_shinfo(skb)->frags[i-1], len); } else if (i < MAX_SKB_FRAGS) { get_page(page); skb_fill_page_desc(skb, i, page, offset, len); } else { err = -EMSGSIZE; goto error; } if (skb->ip_summed == CHECKSUM_NONE) { __wsum csum; csum = csum_page(page, offset, len); skb->csum = csum_block_add(skb->csum, csum, skb->len); } skb->len += len; skb->data_len += len; skb->truesize += len; atomic_add(len, &sk->sk_wmem_alloc); offset += len; size -= len; } return 0; error: cork->length -= size; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); return err; }
DoS +Priv Mem. Corr.
0
ssize_t ip_append_page(struct sock *sk, struct flowi4 *fl4, struct page *page, int offset, size_t size, int flags) { struct inet_sock *inet = inet_sk(sk); struct sk_buff *skb; struct rtable *rt; struct ip_options *opt = NULL; struct inet_cork *cork; int hh_len; int mtu; int len; int err; unsigned int maxfraglen, fragheaderlen, fraggap; if (inet->hdrincl) return -EPERM; if (flags&MSG_PROBE) return 0; if (skb_queue_empty(&sk->sk_write_queue)) return -EINVAL; cork = &inet->cork.base; rt = (struct rtable *)cork->dst; if (cork->flags & IPCORK_OPT) opt = cork->opt; if (!(rt->dst.dev->features&NETIF_F_SG)) return -EOPNOTSUPP; hh_len = LL_RESERVED_SPACE(rt->dst.dev); mtu = cork->fragsize; fragheaderlen = sizeof(struct iphdr) + (opt ? opt->optlen : 0); maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen; if (cork->length + size > 0xFFFF - fragheaderlen) { ip_local_error(sk, EMSGSIZE, fl4->daddr, inet->inet_dport, mtu); return -EMSGSIZE; } if ((skb = skb_peek_tail(&sk->sk_write_queue)) == NULL) return -EINVAL; cork->length += size; if ((size + skb->len > mtu) && (sk->sk_protocol == IPPROTO_UDP) && (rt->dst.dev->features & NETIF_F_UFO)) { skb_shinfo(skb)->gso_size = mtu - fragheaderlen; skb_shinfo(skb)->gso_type = SKB_GSO_UDP; } while (size > 0) { int i; if (skb_is_gso(skb)) len = size; else { /* Check if the remaining data fits into current packet. */ len = mtu - skb->len; if (len < size) len = maxfraglen - skb->len; } if (len <= 0) { struct sk_buff *skb_prev; int alloclen; skb_prev = skb; fraggap = skb_prev->len - maxfraglen; alloclen = fragheaderlen + hh_len + fraggap + 15; skb = sock_wmalloc(sk, alloclen, 1, sk->sk_allocation); if (unlikely(!skb)) { err = -ENOBUFS; goto error; } /* * Fill in the control structures */ skb->ip_summed = CHECKSUM_NONE; skb->csum = 0; skb_reserve(skb, hh_len); /* * Find where to start putting bytes. */ skb_put(skb, fragheaderlen + fraggap); skb_reset_network_header(skb); skb->transport_header = (skb->network_header + fragheaderlen); if (fraggap) { skb->csum = skb_copy_and_csum_bits(skb_prev, maxfraglen, skb_transport_header(skb), fraggap, 0); skb_prev->csum = csum_sub(skb_prev->csum, skb->csum); pskb_trim_unique(skb_prev, maxfraglen); } /* * Put the packet on the pending queue. */ __skb_queue_tail(&sk->sk_write_queue, skb); continue; } i = skb_shinfo(skb)->nr_frags; if (len > size) len = size; if (skb_can_coalesce(skb, i, page, offset)) { skb_frag_size_add(&skb_shinfo(skb)->frags[i-1], len); } else if (i < MAX_SKB_FRAGS) { get_page(page); skb_fill_page_desc(skb, i, page, offset, len); } else { err = -EMSGSIZE; goto error; } if (skb->ip_summed == CHECKSUM_NONE) { __wsum csum; csum = csum_page(page, offset, len); skb->csum = csum_block_add(skb->csum, csum, skb->len); } skb->len += len; skb->data_len += len; skb->truesize += len; atomic_add(len, &sk->sk_wmem_alloc); offset += len; size -= len; } return 0; error: cork->length -= size; IP_INC_STATS(sock_net(sk), IPSTATS_MIB_OUTDISCARDS); return err; }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,693
int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, __be32 saddr, __be32 daddr, struct ip_options_rcu *opt) { struct inet_sock *inet = inet_sk(sk); struct rtable *rt = skb_rtable(skb); struct iphdr *iph; /* Build the IP header. */ skb_push(skb, sizeof(struct iphdr) + (opt ? opt->opt.optlen : 0)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; iph->tos = inet->tos; if (ip_dont_fragment(sk, &rt->dst)) iph->frag_off = htons(IP_DF); else iph->frag_off = 0; iph->ttl = ip_select_ttl(inet, &rt->dst); iph->daddr = (opt && opt->opt.srr ? opt->opt.faddr : daddr); iph->saddr = saddr; iph->protocol = sk->sk_protocol; ip_select_ident(skb, &rt->dst, sk); if (opt && opt->opt.optlen) { iph->ihl += opt->opt.optlen>>2; ip_options_build(skb, &opt->opt, daddr, rt, 0); } skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; /* Send it out. */ return ip_local_out(skb); }
DoS +Priv Mem. Corr.
0
int ip_build_and_send_pkt(struct sk_buff *skb, struct sock *sk, __be32 saddr, __be32 daddr, struct ip_options_rcu *opt) { struct inet_sock *inet = inet_sk(sk); struct rtable *rt = skb_rtable(skb); struct iphdr *iph; /* Build the IP header. */ skb_push(skb, sizeof(struct iphdr) + (opt ? opt->opt.optlen : 0)); skb_reset_network_header(skb); iph = ip_hdr(skb); iph->version = 4; iph->ihl = 5; iph->tos = inet->tos; if (ip_dont_fragment(sk, &rt->dst)) iph->frag_off = htons(IP_DF); else iph->frag_off = 0; iph->ttl = ip_select_ttl(inet, &rt->dst); iph->daddr = (opt && opt->opt.srr ? opt->opt.faddr : daddr); iph->saddr = saddr; iph->protocol = sk->sk_protocol; ip_select_ident(skb, &rt->dst, sk); if (opt && opt->opt.optlen) { iph->ihl += opt->opt.optlen>>2; ip_options_build(skb, &opt->opt, daddr, rt, 0); } skb->priority = sk->sk_priority; skb->mark = sk->sk_mark; /* Send it out. */ return ip_local_out(skb); }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,694
static void ip_copy_addrs(struct iphdr *iph, const struct flowi4 *fl4) { BUILD_BUG_ON(offsetof(typeof(*fl4), daddr) != offsetof(typeof(*fl4), saddr) + sizeof(fl4->saddr)); memcpy(&iph->saddr, &fl4->saddr, sizeof(fl4->saddr) + sizeof(fl4->daddr)); }
DoS +Priv Mem. Corr.
0
static void ip_copy_addrs(struct iphdr *iph, const struct flowi4 *fl4) { BUILD_BUG_ON(offsetof(typeof(*fl4), daddr) != offsetof(typeof(*fl4), saddr) + sizeof(fl4->saddr)); memcpy(&iph->saddr, &fl4->saddr, sizeof(fl4->saddr) + sizeof(fl4->daddr)); }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,695
static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) { to->pkt_type = from->pkt_type; to->priority = from->priority; to->protocol = from->protocol; skb_dst_drop(to); skb_dst_copy(to, from); to->dev = from->dev; to->mark = from->mark; /* Copy the flags to each fragment. */ IPCB(to)->flags = IPCB(from)->flags; #ifdef CONFIG_NET_SCHED to->tc_index = from->tc_index; #endif nf_copy(to, from); #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) to->nf_trace = from->nf_trace; #endif #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) to->ipvs_property = from->ipvs_property; #endif skb_copy_secmark(to, from); }
DoS +Priv Mem. Corr.
0
static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from) { to->pkt_type = from->pkt_type; to->priority = from->priority; to->protocol = from->protocol; skb_dst_drop(to); skb_dst_copy(to, from); to->dev = from->dev; to->mark = from->mark; /* Copy the flags to each fragment. */ IPCB(to)->flags = IPCB(from)->flags; #ifdef CONFIG_NET_SCHED to->tc_index = from->tc_index; #endif nf_copy(to, from); #if IS_ENABLED(CONFIG_NETFILTER_XT_TARGET_TRACE) to->nf_trace = from->nf_trace; #endif #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE) to->ipvs_property = from->ipvs_property; #endif skb_copy_secmark(to, from); }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,696
static inline int ip_finish_output2(struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct rtable *rt = (struct rtable *)dst; struct net_device *dev = dst->dev; unsigned int hh_len = LL_RESERVED_SPACE(dev); struct neighbour *neigh; u32 nexthop; if (rt->rt_type == RTN_MULTICAST) { IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUTMCAST, skb->len); } else if (rt->rt_type == RTN_BROADCAST) IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUTBCAST, skb->len); /* Be paranoid, rather than too clever. */ if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { struct sk_buff *skb2; skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev)); if (skb2 == NULL) { kfree_skb(skb); return -ENOMEM; } if (skb->sk) skb_set_owner_w(skb2, skb->sk); consume_skb(skb); skb = skb2; } rcu_read_lock_bh(); nexthop = (__force u32) rt_nexthop(rt, ip_hdr(skb)->daddr); neigh = __ipv4_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); if (!IS_ERR(neigh)) { int res = dst_neigh_output(dst, neigh, skb); rcu_read_unlock_bh(); return res; } rcu_read_unlock_bh(); net_dbg_ratelimited("%s: No header cache and no neighbour!\n", __func__); kfree_skb(skb); return -EINVAL; }
DoS +Priv Mem. Corr.
0
static inline int ip_finish_output2(struct sk_buff *skb) { struct dst_entry *dst = skb_dst(skb); struct rtable *rt = (struct rtable *)dst; struct net_device *dev = dst->dev; unsigned int hh_len = LL_RESERVED_SPACE(dev); struct neighbour *neigh; u32 nexthop; if (rt->rt_type == RTN_MULTICAST) { IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUTMCAST, skb->len); } else if (rt->rt_type == RTN_BROADCAST) IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUTBCAST, skb->len); /* Be paranoid, rather than too clever. */ if (unlikely(skb_headroom(skb) < hh_len && dev->header_ops)) { struct sk_buff *skb2; skb2 = skb_realloc_headroom(skb, LL_RESERVED_SPACE(dev)); if (skb2 == NULL) { kfree_skb(skb); return -ENOMEM; } if (skb->sk) skb_set_owner_w(skb2, skb->sk); consume_skb(skb); skb = skb2; } rcu_read_lock_bh(); nexthop = (__force u32) rt_nexthop(rt, ip_hdr(skb)->daddr); neigh = __ipv4_neigh_lookup_noref(dev, nexthop); if (unlikely(!neigh)) neigh = __neigh_create(&arp_tbl, &nexthop, dev, false); if (!IS_ERR(neigh)) { int res = dst_neigh_output(dst, neigh, skb); rcu_read_unlock_bh(); return res; } rcu_read_unlock_bh(); net_dbg_ratelimited("%s: No header cache and no neighbour!\n", __func__); kfree_skb(skb); return -EINVAL; }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,697
void ip_flush_pending_frames(struct sock *sk) { __ip_flush_pending_frames(sk, &sk->sk_write_queue, &inet_sk(sk)->cork.base); }
DoS +Priv Mem. Corr.
0
void ip_flush_pending_frames(struct sock *sk) { __ip_flush_pending_frames(sk, &sk->sk_write_queue, &inet_sk(sk)->cork.base); }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,698
int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) { struct iphdr *iph; int ptr; struct net_device *dev; struct sk_buff *skb2; unsigned int mtu, hlen, left, len, ll_rs; int offset; __be16 not_last_frag; struct rtable *rt = skb_rtable(skb); int err = 0; dev = rt->dst.dev; /* * Point into the IP datagram header. */ iph = ip_hdr(skb); if (unlikely(((iph->frag_off & htons(IP_DF)) && !skb->local_df) || (IPCB(skb)->frag_max_size && IPCB(skb)->frag_max_size > dst_mtu(&rt->dst)))) { IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(ip_skb_dst_mtu(skb))); kfree_skb(skb); return -EMSGSIZE; } /* * Setup starting values. */ hlen = iph->ihl * 4; mtu = dst_mtu(&rt->dst) - hlen; /* Size of data space */ #ifdef CONFIG_BRIDGE_NETFILTER if (skb->nf_bridge) mtu -= nf_bridge_mtu_reduction(skb); #endif IPCB(skb)->flags |= IPSKB_FRAG_COMPLETE; /* When frag_list is given, use it. First, check its validity: * some transformers could create wrong frag_list or break existing * one, it is not prohibited. In this case fall back to copying. * * LATER: this step can be merged to real generation of fragments, * we can switch to copy when see the first bad fragment. */ if (skb_has_frag_list(skb)) { struct sk_buff *frag, *frag2; int first_len = skb_pagelen(skb); if (first_len - hlen > mtu || ((first_len - hlen) & 7) || ip_is_fragment(iph) || skb_cloned(skb)) goto slow_path; skb_walk_frags(skb, frag) { /* Correct geometry. */ if (frag->len > mtu || ((frag->len & 7) && frag->next) || skb_headroom(frag) < hlen) goto slow_path_clean; /* Partially cloned skb? */ if (skb_shared(frag)) goto slow_path_clean; BUG_ON(frag->sk); if (skb->sk) { frag->sk = skb->sk; frag->destructor = sock_wfree; } skb->truesize -= frag->truesize; } /* Everything is OK. Generate! */ err = 0; offset = 0; frag = skb_shinfo(skb)->frag_list; skb_frag_list_init(skb); skb->data_len = first_len - skb_headlen(skb); skb->len = first_len; iph->tot_len = htons(first_len); iph->frag_off = htons(IP_MF); ip_send_check(iph); for (;;) { /* Prepare header of the next frame, * before previous one went down. */ if (frag) { frag->ip_summed = CHECKSUM_NONE; skb_reset_transport_header(frag); __skb_push(frag, hlen); skb_reset_network_header(frag); memcpy(skb_network_header(frag), iph, hlen); iph = ip_hdr(frag); iph->tot_len = htons(frag->len); ip_copy_metadata(frag, skb); if (offset == 0) ip_options_fragment(frag); offset += skb->len - hlen; iph->frag_off = htons(offset>>3); if (frag->next != NULL) iph->frag_off |= htons(IP_MF); /* Ready, complete checksum */ ip_send_check(iph); } err = output(skb); if (!err) IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGCREATES); if (err || !frag) break; skb = frag; frag = skb->next; skb->next = NULL; } if (err == 0) { IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGOKS); return 0; } while (frag) { skb = frag->next; kfree_skb(frag); frag = skb; } IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); return err; slow_path_clean: skb_walk_frags(skb, frag2) { if (frag2 == frag) break; frag2->sk = NULL; frag2->destructor = NULL; skb->truesize += frag2->truesize; } } slow_path: /* for offloaded checksums cleanup checksum before fragmentation */ if ((skb->ip_summed == CHECKSUM_PARTIAL) && skb_checksum_help(skb)) goto fail; iph = ip_hdr(skb); left = skb->len - hlen; /* Space per frame */ ptr = hlen; /* Where to start from */ /* for bridged IP traffic encapsulated inside f.e. a vlan header, * we need to make room for the encapsulating header */ ll_rs = LL_RESERVED_SPACE_EXTRA(rt->dst.dev, nf_bridge_pad(skb)); /* * Fragment the datagram. */ offset = (ntohs(iph->frag_off) & IP_OFFSET) << 3; not_last_frag = iph->frag_off & htons(IP_MF); /* * Keep copying data until we run out. */ while (left > 0) { len = left; /* IF: it doesn't fit, use 'mtu' - the data space left */ if (len > mtu) len = mtu; /* IF: we are not sending up to and including the packet end then align the next start on an eight byte boundary */ if (len < left) { len &= ~7; } /* * Allocate buffer. */ if ((skb2 = alloc_skb(len+hlen+ll_rs, GFP_ATOMIC)) == NULL) { NETDEBUG(KERN_INFO "IP: frag: no memory for new fragment!\n"); err = -ENOMEM; goto fail; } /* * Set up data on packet */ ip_copy_metadata(skb2, skb); skb_reserve(skb2, ll_rs); skb_put(skb2, len + hlen); skb_reset_network_header(skb2); skb2->transport_header = skb2->network_header + hlen; /* * Charge the memory for the fragment to any owner * it might possess */ if (skb->sk) skb_set_owner_w(skb2, skb->sk); /* * Copy the packet header into the new buffer. */ skb_copy_from_linear_data(skb, skb_network_header(skb2), hlen); /* * Copy a block of the IP datagram. */ if (skb_copy_bits(skb, ptr, skb_transport_header(skb2), len)) BUG(); left -= len; /* * Fill in the new header fields. */ iph = ip_hdr(skb2); iph->frag_off = htons((offset >> 3)); /* ANK: dirty, but effective trick. Upgrade options only if * the segment to be fragmented was THE FIRST (otherwise, * options are already fixed) and make it ONCE * on the initial skb, so that all the following fragments * will inherit fixed options. */ if (offset == 0) ip_options_fragment(skb); /* * Added AC : If we are fragmenting a fragment that's not the * last fragment then keep MF on each bit */ if (left > 0 || not_last_frag) iph->frag_off |= htons(IP_MF); ptr += len; offset += len; /* * Put this fragment into the sending queue. */ iph->tot_len = htons(len + hlen); ip_send_check(iph); err = output(skb2); if (err) goto fail; IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGCREATES); } consume_skb(skb); IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGOKS); return err; fail: kfree_skb(skb); IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); return err; }
DoS +Priv Mem. Corr.
0
int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *)) { struct iphdr *iph; int ptr; struct net_device *dev; struct sk_buff *skb2; unsigned int mtu, hlen, left, len, ll_rs; int offset; __be16 not_last_frag; struct rtable *rt = skb_rtable(skb); int err = 0; dev = rt->dst.dev; /* * Point into the IP datagram header. */ iph = ip_hdr(skb); if (unlikely(((iph->frag_off & htons(IP_DF)) && !skb->local_df) || (IPCB(skb)->frag_max_size && IPCB(skb)->frag_max_size > dst_mtu(&rt->dst)))) { IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); icmp_send(skb, ICMP_DEST_UNREACH, ICMP_FRAG_NEEDED, htonl(ip_skb_dst_mtu(skb))); kfree_skb(skb); return -EMSGSIZE; } /* * Setup starting values. */ hlen = iph->ihl * 4; mtu = dst_mtu(&rt->dst) - hlen; /* Size of data space */ #ifdef CONFIG_BRIDGE_NETFILTER if (skb->nf_bridge) mtu -= nf_bridge_mtu_reduction(skb); #endif IPCB(skb)->flags |= IPSKB_FRAG_COMPLETE; /* When frag_list is given, use it. First, check its validity: * some transformers could create wrong frag_list or break existing * one, it is not prohibited. In this case fall back to copying. * * LATER: this step can be merged to real generation of fragments, * we can switch to copy when see the first bad fragment. */ if (skb_has_frag_list(skb)) { struct sk_buff *frag, *frag2; int first_len = skb_pagelen(skb); if (first_len - hlen > mtu || ((first_len - hlen) & 7) || ip_is_fragment(iph) || skb_cloned(skb)) goto slow_path; skb_walk_frags(skb, frag) { /* Correct geometry. */ if (frag->len > mtu || ((frag->len & 7) && frag->next) || skb_headroom(frag) < hlen) goto slow_path_clean; /* Partially cloned skb? */ if (skb_shared(frag)) goto slow_path_clean; BUG_ON(frag->sk); if (skb->sk) { frag->sk = skb->sk; frag->destructor = sock_wfree; } skb->truesize -= frag->truesize; } /* Everything is OK. Generate! */ err = 0; offset = 0; frag = skb_shinfo(skb)->frag_list; skb_frag_list_init(skb); skb->data_len = first_len - skb_headlen(skb); skb->len = first_len; iph->tot_len = htons(first_len); iph->frag_off = htons(IP_MF); ip_send_check(iph); for (;;) { /* Prepare header of the next frame, * before previous one went down. */ if (frag) { frag->ip_summed = CHECKSUM_NONE; skb_reset_transport_header(frag); __skb_push(frag, hlen); skb_reset_network_header(frag); memcpy(skb_network_header(frag), iph, hlen); iph = ip_hdr(frag); iph->tot_len = htons(frag->len); ip_copy_metadata(frag, skb); if (offset == 0) ip_options_fragment(frag); offset += skb->len - hlen; iph->frag_off = htons(offset>>3); if (frag->next != NULL) iph->frag_off |= htons(IP_MF); /* Ready, complete checksum */ ip_send_check(iph); } err = output(skb); if (!err) IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGCREATES); if (err || !frag) break; skb = frag; frag = skb->next; skb->next = NULL; } if (err == 0) { IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGOKS); return 0; } while (frag) { skb = frag->next; kfree_skb(frag); frag = skb; } IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); return err; slow_path_clean: skb_walk_frags(skb, frag2) { if (frag2 == frag) break; frag2->sk = NULL; frag2->destructor = NULL; skb->truesize += frag2->truesize; } } slow_path: /* for offloaded checksums cleanup checksum before fragmentation */ if ((skb->ip_summed == CHECKSUM_PARTIAL) && skb_checksum_help(skb)) goto fail; iph = ip_hdr(skb); left = skb->len - hlen; /* Space per frame */ ptr = hlen; /* Where to start from */ /* for bridged IP traffic encapsulated inside f.e. a vlan header, * we need to make room for the encapsulating header */ ll_rs = LL_RESERVED_SPACE_EXTRA(rt->dst.dev, nf_bridge_pad(skb)); /* * Fragment the datagram. */ offset = (ntohs(iph->frag_off) & IP_OFFSET) << 3; not_last_frag = iph->frag_off & htons(IP_MF); /* * Keep copying data until we run out. */ while (left > 0) { len = left; /* IF: it doesn't fit, use 'mtu' - the data space left */ if (len > mtu) len = mtu; /* IF: we are not sending up to and including the packet end then align the next start on an eight byte boundary */ if (len < left) { len &= ~7; } /* * Allocate buffer. */ if ((skb2 = alloc_skb(len+hlen+ll_rs, GFP_ATOMIC)) == NULL) { NETDEBUG(KERN_INFO "IP: frag: no memory for new fragment!\n"); err = -ENOMEM; goto fail; } /* * Set up data on packet */ ip_copy_metadata(skb2, skb); skb_reserve(skb2, ll_rs); skb_put(skb2, len + hlen); skb_reset_network_header(skb2); skb2->transport_header = skb2->network_header + hlen; /* * Charge the memory for the fragment to any owner * it might possess */ if (skb->sk) skb_set_owner_w(skb2, skb->sk); /* * Copy the packet header into the new buffer. */ skb_copy_from_linear_data(skb, skb_network_header(skb2), hlen); /* * Copy a block of the IP datagram. */ if (skb_copy_bits(skb, ptr, skb_transport_header(skb2), len)) BUG(); left -= len; /* * Fill in the new header fields. */ iph = ip_hdr(skb2); iph->frag_off = htons((offset >> 3)); /* ANK: dirty, but effective trick. Upgrade options only if * the segment to be fragmented was THE FIRST (otherwise, * options are already fixed) and make it ONCE * on the initial skb, so that all the following fragments * will inherit fixed options. */ if (offset == 0) ip_options_fragment(skb); /* * Added AC : If we are fragmenting a fragment that's not the * last fragment then keep MF on each bit */ if (left > 0 || not_last_frag) iph->frag_off |= htons(IP_MF); ptr += len; offset += len; /* * Put this fragment into the sending queue. */ iph->tot_len = htons(len + hlen); ip_send_check(iph); err = output(skb2); if (err) goto fail; IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGCREATES); } consume_skb(skb); IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGOKS); return err; fail: kfree_skb(skb); IP_INC_STATS(dev_net(dev), IPSTATS_MIB_FRAGFAILS); return err; }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null
23,699
struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, struct ipcm_cookie *ipc, struct rtable **rtp, unsigned int flags) { struct inet_cork cork; struct sk_buff_head queue; int err; if (flags & MSG_PROBE) return NULL; __skb_queue_head_init(&queue); cork.flags = 0; cork.addr = 0; cork.opt = NULL; err = ip_setup_cork(sk, &cork, ipc, rtp); if (err) return ERR_PTR(err); err = __ip_append_data(sk, fl4, &queue, &cork, &current->task_frag, getfrag, from, length, transhdrlen, flags); if (err) { __ip_flush_pending_frames(sk, &queue, &cork); return ERR_PTR(err); } return __ip_make_skb(sk, fl4, &queue, &cork); }
DoS +Priv Mem. Corr.
0
struct sk_buff *ip_make_skb(struct sock *sk, struct flowi4 *fl4, int getfrag(void *from, char *to, int offset, int len, int odd, struct sk_buff *skb), void *from, int length, int transhdrlen, struct ipcm_cookie *ipc, struct rtable **rtp, unsigned int flags) { struct inet_cork cork; struct sk_buff_head queue; int err; if (flags & MSG_PROBE) return NULL; __skb_queue_head_init(&queue); cork.flags = 0; cork.addr = 0; cork.opt = NULL; err = ip_setup_cork(sk, &cork, ipc, rtp); if (err) return ERR_PTR(err); err = __ip_append_data(sk, fl4, &queue, &cork, &current->task_frag, getfrag, from, length, transhdrlen, flags); if (err) { __ip_flush_pending_frames(sk, &queue, &cork); return ERR_PTR(err); } return __ip_make_skb(sk, fl4, &queue, &cork); }
@@ -772,15 +772,20 @@ static inline int ip_ufo_append_data(struct sock *sk, /* initialize protocol header pointer */ skb->transport_header = skb->network_header + fragheaderlen; - skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; - /* specify the length of each IP datagram fragment */ - skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; - skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + __skb_queue_tail(queue, skb); + } else if (skb_is_gso(skb)) { + goto append; } + skb->ip_summed = CHECKSUM_PARTIAL; + /* specify the length of each IP datagram fragment */ + skb_shinfo(skb)->gso_size = maxfraglen - fragheaderlen; + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + +append: return skb_append_datato_frags(sk, skb, getfrag, from, (length - transhdrlen)); }
CWE-264
null
null