llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT--> @llvm/pr-subscribers-compiler-rt-sanitizer Author: Vitaly Buka (vitalybuka) <details> <summary>Changes</summary> This prevents deadlocks in forked process on essencial runtime components. --- Full diff: https://github.com/llvm/llvm-project/pull/75281.diff 7 Files Affected: - (modified) compiler-rt/lib/lsan/lsan.cpp (+1) - (modified) compiler-rt/lib/lsan/lsan.h (+1) - (modified) compiler-rt/lib/lsan/lsan_common.cpp (+3) - (modified) compiler-rt/lib/lsan/lsan_common.h (+4) - (modified) compiler-rt/lib/lsan/lsan_fuchsia.cpp (+1) - (modified) compiler-rt/lib/lsan/lsan_posix.cpp (+20) - (modified) compiler-rt/test/sanitizer_common/TestCases/Posix/fork_threaded.cpp (+1-1) ``````````diff diff --git a/compiler-rt/lib/lsan/lsan.cpp b/compiler-rt/lib/lsan/lsan.cpp index 6b223603c6a79c..7a27b600f203f7 100644 --- a/compiler-rt/lib/lsan/lsan.cpp +++ b/compiler-rt/lib/lsan/lsan.cpp @@ -101,6 +101,7 @@ extern "C" void __lsan_init() { InstallDeadlySignalHandlers(LsanOnDeadlySignal); InitializeMainThread(); InstallAtExitCheckLeaks(); + InstallAtForkHandler(); InitializeCoverage(common_flags()->coverage, common_flags()->coverage_dir); diff --git a/compiler-rt/lib/lsan/lsan.h b/compiler-rt/lib/lsan/lsan.h index 757edec8e104f9..0074ad5308785c 100644 --- a/compiler-rt/lib/lsan/lsan.h +++ b/compiler-rt/lib/lsan/lsan.h @@ -40,6 +40,7 @@ void InitializeInterceptors(); void ReplaceSystemMalloc(); void LsanOnDeadlySignal(int signo, void *siginfo, void *context); void InstallAtExitCheckLeaks(); +void InstallAtForkHandler(); #define ENSURE_LSAN_INITED \ do { \ diff --git a/compiler-rt/lib/lsan/lsan_common.cpp b/compiler-rt/lib/lsan/lsan_common.cpp index 8b1af5b629fbce..e24839c984b346 100644 --- a/compiler-rt/lib/lsan/lsan_common.cpp +++ b/compiler-rt/lib/lsan/lsan_common.cpp @@ -42,6 +42,9 @@ namespace __lsan { // also to protect the global list of root regions. static Mutex global_mutex; +void LockGlobal() SANITIZER_ACQUIRE(global_mutex) { global_mutex.Lock(); } +void UnlockGlobal() SANITIZER_RELEASE(global_mutex) { global_mutex.Unlock(); } + Flags lsan_flags; void DisableCounterUnderflow() { diff --git a/compiler-rt/lib/lsan/lsan_common.h b/compiler-rt/lib/lsan/lsan_common.h index d3e768363e93b9..c598b62105873e 100644 --- a/compiler-rt/lib/lsan/lsan_common.h +++ b/compiler-rt/lib/lsan/lsan_common.h @@ -120,6 +120,10 @@ void GetRunningThreadsLocked(InternalMmapVector<tid_t> *threads); void LockAllocator(); void UnlockAllocator(); +// Lock/unlock global mutext. +void LockGlobal(); +void UnlockGlobal(); + // Returns the address range occupied by the global allocator object. void GetAllocatorGlobalRange(uptr *begin, uptr *end); // If p points into a chunk that has been allocated to the user, returns its diff --git a/compiler-rt/lib/lsan/lsan_fuchsia.cpp b/compiler-rt/lib/lsan/lsan_fuchsia.cpp index 4edac9757a9c49..ba59bc9b71e332 100644 --- a/compiler-rt/lib/lsan/lsan_fuchsia.cpp +++ b/compiler-rt/lib/lsan/lsan_fuchsia.cpp @@ -80,6 +80,7 @@ void GetAllThreadAllocatorCachesLocked(InternalMmapVector<uptr> *caches) { // On Fuchsia, leak detection is done by a special hook after atexit hooks. // So this doesn't install any atexit hook like on other platforms. void InstallAtExitCheckLeaks() {} +void InstallAtForkHandler() {} // ASan defines this to check its `halt_on_error` flag. bool UseExitcodeOnLeak() { return true; } diff --git a/compiler-rt/lib/lsan/lsan_posix.cpp b/compiler-rt/lib/lsan/lsan_posix.cpp index d99e1cc0105ef7..7dc4254eb150a3 100644 --- a/compiler-rt/lib/lsan/lsan_posix.cpp +++ b/compiler-rt/lib/lsan/lsan_posix.cpp @@ -14,7 +14,11 @@ #include "sanitizer_common/sanitizer_platform.h" #if SANITIZER_POSIX + #include "lsan.h" + +#include <pthread.h> + #include "lsan_allocator.h" #include "lsan_thread.h" #include "sanitizer_common/sanitizer_stacktrace.h" @@ -98,6 +102,22 @@ void InstallAtExitCheckLeaks() { Atexit(DoLeakCheck); } +void InstallAtForkHandler() { + auto before = []() { + LockGlobal(); + LockThreads(); + LockAllocator(); + StackDepotLockAll(); + }; + auto after = []() { + StackDepotUnlockAll(); + UnlockAllocator(); + UnlockThreads(); + UnlockGlobal(); + }; + pthread_atfork(before, after, after); +} + } // namespace __lsan #endif // SANITIZER_POSIX diff --git a/compiler-rt/test/sanitizer_common/TestCases/Posix/fork_threaded.cpp b/compiler-rt/test/sanitizer_common/TestCases/Posix/fork_threaded.cpp index e2d67341846c74..833edbdb54bd93 100644 --- a/compiler-rt/test/sanitizer_common/TestCases/Posix/fork_threaded.cpp +++ b/compiler-rt/test/sanitizer_common/TestCases/Posix/fork_threaded.cpp @@ -1,6 +1,6 @@ // RUN: %clangxx -O0 %s -o %t && %env_tool_opts=die_after_fork=0 %run %t -// UNSUPPORTED: asan, lsan, hwasan +// UNSUPPORTED: asan, hwasan // Forking in multithread environment is unsupported. However we already have // some workarounds, and will add more, so this is the test. `````````` </details> https://github.com/llvm/llvm-project/pull/75281 _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
