[lsan] Report unsuspended threads

[vitalybuka]

Summary

Leak checker needs to suspend all process threads. If we have some running
thread in registry but not suspended we can have false leak report. So we will
report this case here for future debugging.

[vitalybuka]

fix "not found" check

[eugenis]

compiler-rt/lib/lsan/lsan_common.cc

530 ↗

(On Diff #146010)

did you mean CheckThreadLocked? No reason to use function overloading here.

[vitalybuka]

rename

[vitalybuka]

compiler-rt/lib/lsan/lsan_common.cc

530 ↗

(On Diff #146010)

Oh, sure.

[vitalybuka]

better naming

[vitalybuka]

rebase

lib/asan/asan_thread.cc

 void LockThreadRegistry() {
   __asan::asanThreadRegistry().Lock();
 }
 
 void UnlockThreadRegistry() {
   __asan::asanThreadRegistry().Unlock();
 }
 
+ThreadRegistry *GetThreadRegistryLocked() {
+  __asan::asanThreadRegistry().CheckLocked();
+  return &__asan::asanThreadRegistry();
+}
+
 void EnsureMainThreadIDIsCorrect() {
   __asan::EnsureMainThreadIDIsCorrect();
 }
 } // namespace __lsan
 
 // ---------------------- Interface ---------------- {{{1
 using namespace __asan;  // NOLINT
 

lib/lsan/lsan_common.h

#elif defined(__arm__) && \
     SANITIZER_LINUX && !SANITIZER_ANDROID
 #define CAN_SANITIZE_LEAKS 1
 #else
 #define CAN_SANITIZE_LEAKS 0
 #endif
 
 namespace __sanitizer {
 class FlagParser;
+class ThreadRegistry;
 struct DTLS;
 }
 
 namespace __lsan {
 
 // Chunk tags.
 enum ChunkTag {
   kDirectlyLeaked = 0,  // default

 // Wrappers for allocator's ForceLock()/ForceUnlock().
 void LockAllocator();
 void UnlockAllocator();
 // Returns true if [addr, addr + sizeof(void *)) is poisoned.
 bool WordIsPoisoned(uptr addr);
 // Wrappers for ThreadRegistry access.
 void LockThreadRegistry();
 void UnlockThreadRegistry();
+ThreadRegistry *GetThreadRegistryLocked();
 bool GetThreadRangesLocked(tid_t os_id, uptr *stack_begin, uptr *stack_end,
                            uptr *tls_begin, uptr *tls_end, uptr *cache_begin,
                            uptr *cache_end, DTLS **dtls);
 void ForEachExtraStackRange(tid_t os_id, RangeIteratorCallback callback,
                             void *arg);
 // If called from the main thread, updates the main thread's TID in the thread
 // registry. We need this to handle processes that fork() without a subsequent
 // exec(), which invalidates the recorded TID. To update it, we must call

lib/lsan/lsan_common.cc

 // This file is a part of LeakSanitizer.
 // Implementation of common leak checking functionality.
 //
 //===----------------------------------------------------------------------===//
 
 #include "lsan_common.h"
 
 #include "sanitizer_common/sanitizer_common.h"
-#include "sanitizer_common/sanitizer_flags.h"
 #include "sanitizer_common/sanitizer_flag_parser.h"
+#include "sanitizer_common/sanitizer_flags.h"
 #include "sanitizer_common/sanitizer_placement_new.h"
 #include "sanitizer_common/sanitizer_procmaps.h"
+#include "sanitizer_common/sanitizer_report_decorator.h"
 #include "sanitizer_common/sanitizer_stackdepot.h"
 #include "sanitizer_common/sanitizer_stacktrace.h"
 #include "sanitizer_common/sanitizer_suppressions.h"
-#include "sanitizer_common/sanitizer_report_decorator.h"
+#include "sanitizer_common/sanitizer_thread_registry.h"
 #include "sanitizer_common/sanitizer_tls_get_addr.h"
 
 #if CAN_SANITIZE_LEAKS
 namespace __lsan {
 
 // This mutex is used to prevent races between DoLeakCheck and IgnoreObject, and
 // also to protect the global list of root regions.
 BlockingMutex global_mutex(LINKER_INITIALIZED);
static void PrintMatchedSuppressions() {
   Printf("%s\n\n", line);
 }
 
 struct CheckForLeaksParam {
   bool success;
   LeakReport leak_report;
 };
 
+static void ReportIfNotSuspended(ThreadContextBase *tctx, void *arg) {
+  const InternalMmapVector<tid_t> &suspended_threads =
+      *(const InternalMmapVector<tid_t> *)arg;
+  if (tctx->status == ThreadStatusRunning) {
+    uptr i = InternalLowerBound(suspended_threads, 0, suspended_threads.size(),
+                                tctx->os_id, CompareLess<int>());
+    if (i >= suspended_threads.size() || suspended_threads[i] != tctx->os_id)
+      Report("Running thread %d was not suspended. False leaks are possible.\n",
+             tctx->os_id);
+  };
+}
+
+static void ReportUnsuspendedThreads(
+    const SuspendedThreadsList &suspended_threads) {
+  InternalMmapVector<tid_t> threads(suspended_threads.ThreadCount());
+  for (uptr i = 0; i < suspended_threads.ThreadCount(); ++i)
+    threads[i] = suspended_threads.GetThreadID(i);
+
+  Sort(threads.data(), threads.size());
+
+  GetThreadRegistryLocked()->RunCallbackForEachThreadLocked(
+      &ReportIfNotSuspended, &threads);
+}
+
 static void CheckForLeaksCallback(const SuspendedThreadsList &suspended_threads,
                                   void *arg) {
   CheckForLeaksParam *param = reinterpret_cast<CheckForLeaksParam *>(arg);
   CHECK(param);
   CHECK(!param->success);
+  ReportUnsuspendedThreads(suspended_threads);
   ClassifyAllChunks(suspended_threads);
   ForEachChunk(CollectLeaksCb, &param->leak_report);
   // Clean up for subsequent leak checks. This assumes we did not overwrite any
   // kIgnored tags.
   ForEachChunk(ResetTagsCb, nullptr);
   param->success = true;
 }
 

lib/lsan/lsan_thread.cc

 void LockThreadRegistry() {
   thread_registry->Lock();
 }
 
 void UnlockThreadRegistry() {
   thread_registry->Unlock();
 }
 
+ThreadRegistry *GetThreadRegistryLocked() {
+  thread_registry->CheckLocked();
+  return thread_registry;
+}
+
 } // namespace __lsan