Fix memory and buffer leaks on error paths#330
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devdanzin wants to merge 1 commit intopython-lz4:masterfrom
Open
Fix memory and buffer leaks on error paths#330devdanzin wants to merge 1 commit intopython-lz4:masterfrom
devdanzin wants to merge 1 commit intopython-lz4:masterfrom
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Fix memory and buffer leaks on five error paths: - block/compress: release source and dict Py_buffers on PyMem_Malloc failure - block/decompress: release source and dict Py_buffers on PyMem_Malloc failure - frame/compress: release source Py_buffer on block_checksum version error - frame/compress_begin: free destination buffer on LZ4F_compressBegin failure (same pattern as the bug fixed in 43fe65d, not propagated to this site) - frame/__decompress: free original destination buffer on PyMem_Realloc failure (realloc returns NULL without freeing the original pointer) Found using cext-review-toolkit (https://github.com/devdanzin/cext-review-toolkit). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
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Summary
Py_bufferleak inblock.compress()andblock.decompress()whenPyMem_Mallocfails —sourceanddictbuffers not released before returningPyErr_NoMemory()Py_bufferleak inframe.compress()whenblock_checksumis requested on LZ4 < 1.8.0 —sourcebuffer not released before error returndestinationmemory leak inframe.compress_begin()whenLZ4F_compressBeginfails — allocated buffer not freed before error return (same pattern as the bug fixed in commit 43fe65d, not propagated to this site)destinationmemory leak inframe.__decompress()whenPyMem_Reallocfails — original buffer pointer lost on realloc failureContext
These are the same class of bug that was partially fixed in commit 43fe65d. That fix addressed one error path in
__decompressbut missed thePyMem_Reallocfailure path in the same function and the identical pattern incompress_begin.Found using cext-review-toolkit.
Note
This PR was authored and submitted by Claude Code (Anthropic).
It was reviewed by a human before submission.
Test plan