GeezerVison

• Fixes Potential integer overflows in Objects/abstract.c buffer copy APIs #153689

Summary

This PR addresses two integer overflow vulnerabilities explicitly marked by developers with XXX(nnorwitz) in Objects/abstract.c, specifically within PyObject_CopyData when handling the Buffer API.

If a multi-dimensional buffer object is provided with artificially large dimensions or shape array entries, it could wrap around integer variables leading to heap memory corruption or incomplete copy logic.

Changes made

1. Prevent allocation overflow: Added a check to ensure view_src.ndim is within PyBUF_MAX_NDIM before attempting memory allocation for indices, guaranteeing sizeof(Py_ssize_t) * ndim will never integer-overflow.
2. Prevent element count overflow: Added an overflow check within the element counting loop (elements > PY_SSIZE_T_MAX / view_src.shape[k]) that returns a standard BufferError instead of overflowing the Py_ssize_t counter.

The appropriate blurb entry for Misc/NEWS.d has been generated and included in this commit.

• Issue: Potential integer overflows in Objects/abstract.c buffer copy APIs #153689