1 //===-- ubsan_type_hash_win.cc --------------------------------------------===//
3 // This file is distributed under the University of Illinois Open Source
4 // License. See LICENSE.TXT for details.
6 //===----------------------------------------------------------------------===//
8 // Implementation of type hashing/lookup for Microsoft C++ ABI.
10 //===----------------------------------------------------------------------===//
12 #include "sanitizer_common/sanitizer_platform.h"
13 #include "ubsan_platform.h"
14 #if CAN_SANITIZE_UB && SANITIZER_WINDOWS
15 #include "ubsan_type_hash.h"
17 #include "sanitizer_common/sanitizer_common.h"
21 struct CompleteObjectLocator
{
22 int is_image_relative
;
30 struct CompleteObjectLocatorAbs
{
31 int is_image_relative
;
34 std::type_info
*rtti_addr
;
36 CompleteObjectLocator
*obj_locator_addr
;
39 bool __ubsan::checkDynamicType(void *Object
, void *Type
, HashValue Hash
) {
44 __ubsan::DynamicTypeInfo
45 __ubsan::getDynamicTypeInfoFromVtable(void *VtablePtr
) {
46 // The virtual table may not have a complete object locator if the object
47 // was compiled without RTTI (i.e. we might be reading from some other global
48 // laid out before the virtual table), so we need to carefully validate each
49 // pointer dereference and perform sanity checks.
50 CompleteObjectLocator
**obj_locator_ptr
=
51 ((CompleteObjectLocator
**)VtablePtr
)-1;
52 if (!IsAccessibleMemoryRange((uptr
)obj_locator_ptr
, sizeof(void*)))
53 return DynamicTypeInfo(0, 0, 0);
55 CompleteObjectLocator
*obj_locator
= *obj_locator_ptr
;
56 if (!IsAccessibleMemoryRange((uptr
)obj_locator
,
57 sizeof(CompleteObjectLocator
)))
58 return DynamicTypeInfo(0, 0, 0);
60 std::type_info
*tinfo
;
61 if (obj_locator
->is_image_relative
== 1) {
62 char *image_base
= ((char *)obj_locator
) - obj_locator
->obj_locator_addr
;
63 tinfo
= (std::type_info
*)(image_base
+ obj_locator
->rtti_addr
);
64 } else if (obj_locator
->is_image_relative
== 0)
65 tinfo
= ((CompleteObjectLocatorAbs
*)obj_locator
)->rtti_addr
;
67 // Probably not a complete object locator.
68 return DynamicTypeInfo(0, 0, 0);
70 if (!IsAccessibleMemoryRange((uptr
)tinfo
, sizeof(std::type_info
)))
71 return DynamicTypeInfo(0, 0, 0);
73 // Okay, this is probably a std::type_info. Request its name.
74 // FIXME: Implement a base class search like we do for Itanium.
75 return DynamicTypeInfo(tinfo
->name(), obj_locator
->offset_to_top
,
79 #endif // CAN_SANITIZE_UB && SANITIZER_WINDOWS