Add C++17 aligned new/delete entrypoints to libasan

Jakub Jelinek via llvm-commits llvm-commits at lists.llvm.org
Mon Sep 19 07:17:56 PDT 2016


Hi!

This is the shorter version of http://gcc.gnu.org/PR77567 changes, which
just adds the C++17 operator new/delete/new[]/delete[] entrypoints with
std::align_val_t arguments, but doesn't verify the C++17 requirement that
non-std::align_val_t allocation isn't mixed with std::align_val_t
deallocation and vice versa, because there are no bits left right now in the
libasan structures to record this, but at least it complains if you
malloc/memalign and deallocate using delete operator with std::align_val_t,
etc.

--- compiler-rt/lib/asan/asan_new_delete.cc.jj	2016-05-17 10:47:05.000000000 +0200
+++ compiler-rt/lib/asan/asan_new_delete.cc	2016-09-13 17:44:13.428306595 +0200
@@ -45,17 +45,30 @@
 
 using namespace __asan;  // NOLINT
 
+// FreeBSD prior v9.2 have wrong definition of 'size_t'.
+// http://svnweb.freebsd.org/base?view=revision&revision=232261
+#if SANITIZER_FREEBSD && SANITIZER_WORDSIZE == 32
+#include <sys/param.h>
+#if __FreeBSD_version <= 902001  // v9.2
+#define size_t unsigned
+#endif  // __FreeBSD_version
+#endif  // SANITIZER_FREEBSD && SANITIZER_WORDSIZE == 32
+
 // This code has issues on OSX.
 // See https://github.com/google/sanitizers/issues/131.
 
-// Fake std::nothrow_t to avoid including <new>.
+// Fake std::nothrow_t and std::align_val_t to avoid including <new>.
 namespace std {
 struct nothrow_t {};
+enum class align_val_t: size_t {};
 }  // namespace std
 
 #define OPERATOR_NEW_BODY(type) \
   GET_STACK_TRACE_MALLOC;\
   return asan_memalign(0, size, &stack, type);
+#define OPERATOR_NEW_BODY_ALIGN(type) \
+  GET_STACK_TRACE_MALLOC;\
+  return asan_memalign((uptr)align, size, &stack, type);
 
 // On OS X it's not enough to just provide our own 'operator new' and
 // 'operator delete' implementations, because they're going to be in the
@@ -65,15 +78,6 @@ struct nothrow_t {};
 // To make sure that C++ allocation/deallocation operators are overridden on
 // OS X we need to intercept them using their mangled names.
 #if !SANITIZER_MAC
-// FreeBSD prior v9.2 have wrong definition of 'size_t'.
-// http://svnweb.freebsd.org/base?view=revision&revision=232261
-#if SANITIZER_FREEBSD && SANITIZER_WORDSIZE == 32
-#include <sys/param.h>
-#if __FreeBSD_version <= 902001  // v9.2
-#define size_t unsigned
-#endif  // __FreeBSD_version
-#endif  // SANITIZER_FREEBSD && SANITIZER_WORDSIZE == 32
-
 CXX_OPERATOR_ATTRIBUTE
 void *operator new(size_t size) { OPERATOR_NEW_BODY(FROM_NEW); }
 CXX_OPERATOR_ATTRIBUTE
@@ -84,6 +88,18 @@ void *operator new(size_t size, std::not
 CXX_OPERATOR_ATTRIBUTE
 void *operator new[](size_t size, std::nothrow_t const&)
 { OPERATOR_NEW_BODY(FROM_NEW_BR); }
+CXX_OPERATOR_ATTRIBUTE
+void *operator new(size_t size, std::align_val_t align)
+{ OPERATOR_NEW_BODY_ALIGN(FROM_NEW); }
+CXX_OPERATOR_ATTRIBUTE
+void *operator new[](size_t size, std::align_val_t align)
+{ OPERATOR_NEW_BODY_ALIGN(FROM_NEW_BR); }
+CXX_OPERATOR_ATTRIBUTE
+void *operator new(size_t size, std::align_val_t align, std::nothrow_t const&)
+{ OPERATOR_NEW_BODY_ALIGN(FROM_NEW); }
+CXX_OPERATOR_ATTRIBUTE
+void *operator new[](size_t size, std::align_val_t align, std::nothrow_t const&)
+{ OPERATOR_NEW_BODY_ALIGN(FROM_NEW_BR); }
 
 #else  // SANITIZER_MAC
 INTERCEPTOR(void *, _Znwm, size_t size) {
@@ -131,6 +147,32 @@ void operator delete[](void *ptr, size_t
   GET_STACK_TRACE_FREE;
   asan_sized_free(ptr, size, &stack, FROM_NEW_BR);
 }
+CXX_OPERATOR_ATTRIBUTE
+void operator delete(void *ptr, std::align_val_t) NOEXCEPT {
+  OPERATOR_DELETE_BODY(FROM_NEW);
+}
+CXX_OPERATOR_ATTRIBUTE
+void operator delete[](void *ptr, std::align_val_t) NOEXCEPT {
+  OPERATOR_DELETE_BODY(FROM_NEW_BR);
+}
+CXX_OPERATOR_ATTRIBUTE
+void operator delete(void *ptr, std::align_val_t, std::nothrow_t const&) {
+  OPERATOR_DELETE_BODY(FROM_NEW);
+}
+CXX_OPERATOR_ATTRIBUTE
+void operator delete[](void *ptr, std::align_val_t, std::nothrow_t const&) {
+  OPERATOR_DELETE_BODY(FROM_NEW_BR);
+}
+CXX_OPERATOR_ATTRIBUTE
+void operator delete(void *ptr, size_t size, std::align_val_t) NOEXCEPT {
+  GET_STACK_TRACE_FREE;
+  asan_sized_free(ptr, size, &stack, FROM_NEW);
+}
+CXX_OPERATOR_ATTRIBUTE
+void operator delete[](void *ptr, size_t size, std::align_val_t) NOEXCEPT {
+  GET_STACK_TRACE_FREE;
+  asan_sized_free(ptr, size, &stack, FROM_NEW_BR);
+}
 
 #else  // SANITIZER_MAC
 INTERCEPTOR(void, _ZdlPv, void *ptr) {

	Jakub


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