bpo-36389: _PyObject_IsFreed() now also detects uninitialized memory #12770
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Replace _PyMem_IsFreed() function with _PyMem_IsPtrFreed() inline function. The function is now way more efficient, it became a simple comparison on integers, rather than a short loop. Add unit tests on _PyObject_IsFreed().
vstinner
added a commit
that referenced
this pull request
Apr 11, 2019
…emory (GH-12770) (GH-12788) * bpo-36389: _PyObject_IsFreed() now also detects uninitialized memory (GH-12770) Replace _PyMem_IsFreed() function with _PyMem_IsPtrFreed() inline function. The function is now way more efficient, it became a simple comparison on integers, rather than a short loop. It detects also uninitialized bytes and "forbidden bytes" filled by debug hooks on memory allocators. Add unit tests on _PyObject_IsFreed(). (cherry picked from commit 2b00db6) * bpo-36389: Change PyMem_SetupDebugHooks() constants (GH-12782) Modify CLEANBYTE, DEADDYTE and FORBIDDENBYTE constants: use 0xCD, 0xDD and 0xFD, rather than 0xCB, 0xBB and 0xFB, to use the same byte patterns than Windows CRT debug malloc() and free(). (cherry picked from commit 4c409be)
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Replace _PyMem_IsFreed() function with _PyMem_IsPtrFreed() inline
function. The function is now way more efficient, it became a simple
comparison on integers, rather than a short loop.
https://bugs.python.org/issue36389