Add mutex

Author: thurstond

compiler-rt/lib/asan/asan_errors.cpp

@@ -612,7 +612,7 @@ static void CheckPoisonRecords(uptr addr) {
   if (poison_magic != kAsanUserPoisonedMemoryMagic)
     return;
 
-  PoisonRecordRingBuffer *PoisonRecord = GetPoisonRecord();
+  PoisonRecordRingBuffer *PoisonRecord = AcquirePoisonRecords();
   if (PoisonRecord) {
     bool FoundMatch = false;
 
@@ -637,6 +637,7 @@ static void CheckPoisonRecords(uptr addr) {
       Printf("Try setting a larger track_poison value.\n");
     }
   }
+  ReleasePoisonRecords();
 }
 
 void ErrorGeneric::Print() {

compiler-rt/lib/asan/asan_poisoning.cpp

@@ -26,6 +26,7 @@ namespace __asan {
 
 static atomic_uint8_t can_poison_memory;
 
+static Mutex PoisonRecordsMutex;
 static PoisonRecordRingBuffer *PoisonRecords = nullptr;
 
 void InitializePoisonTracking() {
@@ -35,10 +36,16 @@ void InitializePoisonTracking() {
   PoisonRecords = PoisonRecordRingBuffer::New(flags()->track_poison);
 }
 
-PoisonRecordRingBuffer* GetPoisonRecord() {
+PoisonRecordRingBuffer* SANITIZER_ACQUIRE(PoisonRecordsMutex) AcquirePoisonRecords() {
+  PoisonRecordsMutex.Lock();
+
   return PoisonRecords;
 }
 
+void SANITIZER_RELEASE(PoisonRecordsMutex) ReleasePoisonRecords() {
+  PoisonRecordsMutex.Unlock();
+}
+
 void SetCanPoisonMemory(bool value) {
   atomic_store(&can_poison_memory, value, memory_order_release);
 }
@@ -136,8 +143,8 @@ void __asan_poison_memory_region(void const volatile *addr, uptr size) {
                         .thread_id = current_tid,
                         .begin = beg_addr,
                         .end = end_addr};
-    // TODO: mutex
-    GetPoisonRecord()->push(record);
+    AcquirePoisonRecords()->push(record);
+    ReleasePoisonRecords();
   }
 
   ShadowSegmentEndpoint beg(beg_addr);

compiler-rt/lib/asan/asan_poisoning.h

@@ -10,6 +10,7 @@
 //
 // Shadow memory poisoning by ASan RTL and by user application.
 //===----------------------------------------------------------------------===//
+
 #ifndef ASAN_POISONING_H
 #define ASAN_POISONING_H
 
@@ -37,7 +38,8 @@ using PoisonRecordRingBuffer = RingBuffer<struct PoisonRecord>;
 // Set up data structures for track_poison.
 void InitializePoisonTracking();
 
-PoisonRecordRingBuffer* GetPoisonRecord();
+PoisonRecordRingBuffer* AcquirePoisonRecords();
+void ReleasePoisonRecords();
 
 // Enable/disable memory poisoning.
 void SetCanPoisonMemory(bool value);