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