1 files changed, 26 insertions, 0 deletions
diff --git a/libsanitizer/sanitizer_common/sanitizer_common.cc b/libsanitizer/sanitizer_common/sanitizer_common.cc
index 76a55c0f8b4..96e8808f6d1 100644
--- a/libsanitizer/sanitizer_common/sanitizer_common.cc
+++ b/libsanitizer/sanitizer_common/sanitizer_common.cc
@@ -153,6 +153,27 @@ void SortArray(uptr *array, uptr size) {
   }
 }
 
+// We want to map a chunk of address space aligned to 'alignment'.
+// We do it by maping a bit more and then unmaping redundant pieces.
+// We probably can do it with fewer syscalls in some OS-dependent way.
+void *MmapAlignedOrDie(uptr size, uptr alignment, const char *mem_type) {
+// uptr PageSize = GetPageSizeCached();
+  CHECK(IsPowerOfTwo(size));
+  CHECK(IsPowerOfTwo(alignment));
+  uptr map_size = size + alignment;
+  uptr map_res = (uptr)MmapOrDie(map_size, mem_type);
+  uptr map_end = map_res + map_size;
+  uptr res = map_res;
+  if (res & (alignment - 1))  // Not aligned.
+    res = (map_res + alignment) & ~(alignment - 1);
+  uptr end = res + size;
+  if (res != map_res)
+    UnmapOrDie((void*)map_res, res - map_res);
+  if (end != map_end)
+    UnmapOrDie((void*)end, map_end - end);
+  return (void*)res;
+}
+
 }  // namespace __sanitizer
 
 using namespace __sanitizer;  // NOLINT
@@ -178,4 +199,9 @@ void __sanitizer_set_report_fd(int fd) {
     internal_close(report_fd);
   report_fd = fd;
 }
+
+void NOINLINE __sanitizer_sandbox_on_notify(void *reserved) {
+  (void)reserved;
+  PrepareForSandboxing();
+}
 }  // extern "C"