diff --git a/compiler-rt/lib/lsan/lsan_allocator.cpp b/compiler-rt/lib/lsan/lsan_allocator.cpp
--- a/compiler-rt/lib/lsan/lsan_allocator.cpp
+++ b/compiler-rt/lib/lsan/lsan_allocator.cpp
@@ -375,6 +375,7 @@
   if (beg == nullptr) return 0;
   ChunkMetadata *m = Metadata(beg);
   if (m == nullptr) return 0;
+  if (!m->allocated) return 0;
   if (m->requested_size == 0) return 0;
   *start = (void*)beg;
   *size = m->requested_size;