diff --git a/lib/tsan/rtl/tsan_rtl.cc b/lib/tsan/rtl/tsan_rtl.cc
index 962c07a..3860073 100644
--- a/lib/tsan/rtl/tsan_rtl.cc
+++ b/lib/tsan/rtl/tsan_rtl.cc
@@ -433,9 +433,11 @@
     addr += offset;
     size -= offset;
   }
-  CHECK_EQ(addr % 8, 0);
-  CHECK(IsAppMem(addr));
-  CHECK(IsAppMem(addr + size - 1));
+  DCHECK_EQ(addr % 8, 0);
+  // If a user passes some insane arguments (memset(0)),
+  // let it just crash as usual.
+  if (!IsAppMem(addr) || !IsAppMem(addr + size - 1))
+    return;
   (void)thr;
   (void)pc;
   // Some programs mmap like hundreds of GBs but actually used a small part.