1//===-- ubsan_type_hash_win.cpp -------------------------------------------===// 2// 3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4// See https://llvm.org/LICENSE.txt for license information. 5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6// 7//===----------------------------------------------------------------------===// 8// 9// Implementation of type hashing/lookup for Microsoft C++ ABI. 10// 11//===----------------------------------------------------------------------===// 12 13#include "sanitizer_common/sanitizer_platform.h" 14#include "ubsan_platform.h" 15#if CAN_SANITIZE_UB && defined(_MSC_VER) 16#include "ubsan_type_hash.h" 17 18#include "sanitizer_common/sanitizer_common.h" 19 20#include <typeinfo> 21 22struct CompleteObjectLocator { 23 int is_image_relative; 24 int offset_to_top; 25 int vfptr_offset; 26 int rtti_addr; 27 int chd_addr; 28 int obj_locator_addr; 29}; 30 31struct CompleteObjectLocatorAbs { 32 int is_image_relative; 33 int offset_to_top; 34 int vfptr_offset; 35 std::type_info *rtti_addr; 36 void *chd_addr; 37 CompleteObjectLocator *obj_locator_addr; 38}; 39 40bool __ubsan::checkDynamicType(void *Object, void *Type, HashValue Hash) { 41 // FIXME: Implement. 42 return false; 43} 44 45__ubsan::DynamicTypeInfo 46__ubsan::getDynamicTypeInfoFromVtable(void *VtablePtr) { 47 // The virtual table may not have a complete object locator if the object 48 // was compiled without RTTI (i.e. we might be reading from some other global 49 // laid out before the virtual table), so we need to carefully validate each 50 // pointer dereference and perform sanity checks. 51 CompleteObjectLocator **obj_locator_ptr = 52 ((CompleteObjectLocator**)VtablePtr)-1; 53 if (!IsAccessibleMemoryRange((uptr)obj_locator_ptr, sizeof(void*))) 54 return DynamicTypeInfo(0, 0, 0); 55 56 CompleteObjectLocator *obj_locator = *obj_locator_ptr; 57 if (!IsAccessibleMemoryRange((uptr)obj_locator, 58 sizeof(CompleteObjectLocator))) 59 return DynamicTypeInfo(0, 0, 0); 60 61 std::type_info *tinfo; 62 if (obj_locator->is_image_relative == 1) { 63 char *image_base = ((char *)obj_locator) - obj_locator->obj_locator_addr; 64 tinfo = (std::type_info *)(image_base + obj_locator->rtti_addr); 65 } else if (obj_locator->is_image_relative == 0) 66 tinfo = ((CompleteObjectLocatorAbs *)obj_locator)->rtti_addr; 67 else 68 // Probably not a complete object locator. 69 return DynamicTypeInfo(0, 0, 0); 70 71 if (!IsAccessibleMemoryRange((uptr)tinfo, sizeof(std::type_info))) 72 return DynamicTypeInfo(0, 0, 0); 73 74 // Okay, this is probably a std::type_info. Request its name. 75 // FIXME: Implement a base class search like we do for Itanium. 76 return DynamicTypeInfo(tinfo->name(), obj_locator->offset_to_top, 77 "<unknown>"); 78} 79 80bool __ubsan::checkTypeInfoEquality(const void *, const void *) { 81 return false; 82} 83 84#endif // CAN_SANITIZE_UB && SANITIZER_WINDOWS 85