diff --git a/compiler-rt/lib/asan/asan_allocator.cpp b/compiler-rt/lib/asan/asan_allocator.cpp
index 3a55c2af65653..8a56132bf946a 100644
--- a/compiler-rt/lib/asan/asan_allocator.cpp
+++ b/compiler-rt/lib/asan/asan_allocator.cpp
@@ -797,8 +797,10 @@ struct Allocator {
   void ReportInvalidFree(void *ptr, u8 chunk_state, BufferedStackTrace *stack) {
     if (chunk_state == CHUNK_QUARANTINE)
       ReportDoubleFree((uptr)ptr, stack);
-    else
-      ReportFreeNotMalloced((uptr)ptr, stack);
+    else {
+      if (common_flags()->enable_unmalloced_free_check)
+        ReportFreeNotMalloced((uptr)ptr, stack);
+    }
   }
 
   void CommitBack(AsanThreadLocalMallocStorage *ms, BufferedStackTrace *stack) {
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc b/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc
index c1e3530618c20..e7d0f3a6d6496 100644
--- a/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_flags.inc
@@ -282,3 +282,6 @@ COMMON_FLAG(bool, enable_symbolizer_markup, SANITIZER_FUCHSIA,
 
 COMMON_FLAG(bool, detect_invalid_join, true,
             "If set, check invalid joins of threads.")
+COMMON_FLAG(bool, enable_unmalloced_free_check, !SANITIZER_AIX,
+            "if true, FreeNotMalloced error will be reported. Only disable "
+            "this error detecting on AIX by default for now.")