1 files changed, 47 insertions, 6 deletions

diff --git a/compiler-rt/lib/asan/asan_report.cc b/compiler-rt/lib/asan/asan_report.cc
index 42fae9c73f0..e3bc02994ef 100644
--- a/compiler-rt/lib/asan/asan_report.cc
+++ b/compiler-rt/lib/asan/asan_report.cc
@@ -298,17 +298,58 @@ static NOINLINE void ReportInvalidPointerPair(uptr pc, uptr bp, uptr sp,
   in_report.ReportError(error);
 }
 
+static bool IsInvalidPointerPair(uptr a1, uptr a2) {
+  if (a1 == a2)
+    return false;
+
+  // 256B in shadow memory can be iterated quite fast
+  static const uptr kMaxOffset = 2048;
+
+  uptr left = a1 < a2 ? a1 : a2;
+  uptr right = a1 < a2 ? a2 : a1;
+  uptr offset = right - left;
+  if (offset <= kMaxOffset)
+    return __asan_region_is_poisoned(left, offset);
+
+  AsanThread *t = GetCurrentThread();
+
+  // check whether left is a stack memory pointer
+  if (uptr shadow_offset1 = t->GetStackVariableShadowStart(left)) {
+    uptr shadow_offset2 = t->GetStackVariableShadowStart(right);
+    return shadow_offset2 == 0 || shadow_offset1 != shadow_offset2;
+  }
+
+  // check whether left is a heap memory address
+  HeapAddressDescription hdesc1, hdesc2;
+  if (GetHeapAddressInformation(left, 0, &hdesc1) &&
+      hdesc1.chunk_access.access_type == kAccessTypeInside)
+    return !GetHeapAddressInformation(right, 0, &hdesc2) ||
+        hdesc2.chunk_access.access_type != kAccessTypeInside ||
+        hdesc1.chunk_access.chunk_begin != hdesc2.chunk_access.chunk_begin;
+
+  // check whether left is an address of a global variable
+  GlobalAddressDescription gdesc1, gdesc2;
+  if (GetGlobalAddressInformation(left, 0, &gdesc1))
+    return !GetGlobalAddressInformation(right - 1, 0, &gdesc2) ||
+        !gdesc1.PointsInsideTheSameVariable(gdesc2);
+
+  if (t->GetStackVariableShadowStart(right) ||
+      GetHeapAddressInformation(right, 0, &hdesc2) ||
+      GetGlobalAddressInformation(right - 1, 0, &gdesc2))
+    return true;
+
+  // At this point we know nothing about both a1 and a2 addresses.
+  return false;
+}
+
 static INLINE void CheckForInvalidPointerPair(void *p1, void *p2) {
   if (!flags()->detect_invalid_pointer_pairs) return;
   uptr a1 = reinterpret_cast<uptr>(p1);
   uptr a2 = reinterpret_cast<uptr>(p2);
-  AsanChunkView chunk1 = FindHeapChunkByAddress(a1);
-  AsanChunkView chunk2 = FindHeapChunkByAddress(a2);
-  bool valid1 = chunk1.IsAllocated();
-  bool valid2 = chunk2.IsAllocated();
-  if (!valid1 || !valid2 || !chunk1.Eq(chunk2)) {
+
+  if (IsInvalidPointerPair(a1, a2)) {
     GET_CALLER_PC_BP_SP;
-    return ReportInvalidPointerPair(pc, bp, sp, a1, a2);
+    ReportInvalidPointerPair(pc, bp, sp, a1, a2);
   }
 }
 // ----------------------- Mac-specific reports ----------------- {{{1