1 files changed, 50 insertions, 0 deletions
diff --git a/lib/hwasan/hwasan_malloc_bisect.h b/lib/hwasan/hwasan_malloc_bisect.h
new file mode 100644
index 000000000000..eaf124aab7dd
--- /dev/null
+++ b/lib/hwasan/hwasan_malloc_bisect.h
@@ -0,0 +1,50 @@
+//===-- hwasan_malloc_bisect.h ----------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of HWAddressSanitizer.
+//
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_common/sanitizer_hash.h"
+#include "hwasan.h"
+
+namespace __hwasan {
+
+static u32 malloc_hash(StackTrace *stack, uptr orig_size) {
+  uptr len = Min(stack->size, (unsigned)7);
+  MurMur2HashBuilder H(len);
+  H.add(orig_size);
+  // Start with frame #1 to skip __sanitizer_malloc frame, which is
+  // (a) almost always the same (well, could be operator new or new[])
+  // (b) can change hashes when compiler-rt is rebuilt, invalidating previous
+  // bisection results.
+  // Because of ASLR, use only offset inside the page.
+  for (uptr i = 1; i < len; ++i) H.add(((u32)stack->trace[i]) & 0xFFF);
+  return H.get();
+}
+
+static INLINE bool malloc_bisect(StackTrace *stack, uptr orig_size) {
+  uptr left = flags()->malloc_bisect_left;
+  uptr right = flags()->malloc_bisect_right;
+  if (LIKELY(left == 0 && right == 0))
+    return true;
+  if (!stack)
+    return true;
+  // Allow malloc_bisect_right > (u32)(-1) to avoid spelling the latter in
+  // decimal.
+  uptr h = (uptr)malloc_hash(stack, orig_size);
+  if (h < left || h > right)
+    return false;
+  if (flags()->malloc_bisect_dump) {
+    Printf("[alloc] %u %zu\n", h, orig_size);
+    stack->Print();
+  }
+  return true;
+}
+
+}  // namespace __hwasan