htdy7703/pytorch-mobile-list-construct-stack-underflow-poc-20260709

PyTorch mobile LIST_CONSTRUCT stack underflow PoC

This repository demonstrates a stack-underflow crash in PyTorch's lite-interpreter bytecode runtime.

What this PoC shows:

• a valid .ptl model can be mutated by changing only one serialized LIST_CONSTRUCT arity operand
• the original model still runs normally when LIST_CONSTRUCT.N stays at 2
• changing LIST_CONSTRUCT.N from 2 to 3 makes forward() crash the official torch-2.13.0+cpu wheel with SIGSEGV
• the malformed model reproduces through both BytesIO and file-path loads

What this PoC does not show:

• a stable memory disclosure primitive
• code execution
• a claim about every TorchScript loading path

Verified runtime:

• official torch-2.13.0+cpu wheel

Run:

python3 poc_mobile_list_construct_stack_underflow.py --list-n 2
python3 poc_mobile_list_construct_stack_underflow.py --list-n 3