[libc-commits] [PATCH] D99598: [libc] Fix msan/asan memcpy reentrancy

[Guillaume Chatelet via Phabricator via libc-commits]

gchatelet created this revision.
gchatelet added a reviewer: sivachandra.
Herald added subscribers: libc-commits, ecnelises, tschuett, mgorny.
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This is needed to prevent asan/msan instrumentation to redirect CopyBlock to `__asan_memcpy` (resp. `__msan_memcpy`).
These functions would then differ operation to `memcpy` which leads to reentrancy issues.

With this patch, `memcpy` is fully instrumented and covered by asan/msan.

If this turns out to be too expensive, instrumentation can be selectively or fully disabled through the use of the `__attribute__((no_sanitize(address, memory)))` annotation.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D99598

Files:
  libc/src/__support/CMakeLists.txt
  libc/src/__support/sanitizer.h
  libc/src/__support/sanitizer_annotations.h
  libc/src/string/memory_utils/memcpy_utils.h
  libc/utils/FPUtil/x86_64/FEnv.h

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