[Sanitizers] Operator new() interceptors always die on allocation error

Summary:
Operator new interceptors behavior is now controlled by their nothrow
property as well as by allocator_may_return_null flag value:

- allocator_may_return_null=* + new()        - die on allocation error
- allocator_may_return_null=0 + new(nothrow) - die on allocation error
- allocator_may_return_null=1 + new(nothrow) - return null

Ideally new() should throw std::bad_alloc exception, but that is not
trivial to achieve, hence TODO.

Reviewers: eugenis

Subscribers: kubamracek, llvm-commits

Differential Revision: https://reviews.llvm.org/D34731

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@306604 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 14 insertions, 6 deletions

diff --git a/lib/msan/msan_new_delete.cc b/lib/msan/msan_new_delete.cc
index 540100316..c7295feeb 100644
--- a/lib/msan/msan_new_delete.cc
+++ b/lib/msan/msan_new_delete.cc
@@ -14,6 +14,7 @@
 
 #include "msan.h"
 #include "interception/interception.h"
+#include "sanitizer_common/sanitizer_allocator.h"
 
 #if MSAN_REPLACE_OPERATORS_NEW_AND_DELETE
 
@@ -27,18 +28,25 @@ namespace std {
 }  // namespace std
 
 
-#define OPERATOR_NEW_BODY \
+// TODO(alekseys): throw std::bad_alloc instead of dying on OOM.
+#define OPERATOR_NEW_BODY(nothrow) \
   GET_MALLOC_STACK_TRACE; \
-  return MsanReallocate(&stack, 0, size, sizeof(u64), false)
+  void *res = MsanReallocate(&stack, 0, size, sizeof(u64), false);\
+  if (!nothrow && UNLIKELY(!res)) DieOnFailure::OnOOM();\
+  return res
 
 INTERCEPTOR_ATTRIBUTE
-void *operator new(size_t size) { OPERATOR_NEW_BODY; }
+void *operator new(size_t size) { OPERATOR_NEW_BODY(false /*nothrow*/); }
 INTERCEPTOR_ATTRIBUTE
-void *operator new[](size_t size) { OPERATOR_NEW_BODY; }
+void *operator new[](size_t size) { OPERATOR_NEW_BODY(false /*nothrow*/); }
 INTERCEPTOR_ATTRIBUTE
-void *operator new(size_t size, std::nothrow_t const&) { OPERATOR_NEW_BODY; }
+void *operator new(size_t size, std::nothrow_t const&) {
+  OPERATOR_NEW_BODY(true /*nothrow*/);
+}
 INTERCEPTOR_ATTRIBUTE
-void *operator new[](size_t size, std::nothrow_t const&) { OPERATOR_NEW_BODY; }
+void *operator new[](size_t size, std::nothrow_t const&) {
+  OPERATOR_NEW_BODY(true /*nothrow*/);
+}
 
 #define OPERATOR_DELETE_BODY \
   GET_MALLOC_STACK_TRACE; \