1 //===-- asan_malloc_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 // This file is a part of AddressSanitizer, an address sanity checker. 11 // 12 // Windows-specific malloc interception. 13 //===----------------------------------------------------------------------===// 14 #ifdef _WIN32 15 16 #include "asan_allocator.h" 17 #include "asan_interceptors.h" 18 #include "asan_internal.h" 19 #include "asan_stack.h" 20 21 #include "interception/interception.h" 22 23 // ---------------------- Replacement functions ---------------- {{{1 24 using namespace __asan; // NOLINT 25 26 // FIXME: Simply defining functions with the same signature in *.obj 27 // files overrides the standard functions in *.lib 28 // This works well for simple helloworld-like tests but might need to be 29 // revisited in the future. 30 31 extern "C" { 32 void free(void *ptr) { 33 GET_STACK_TRACE_HERE_FOR_FREE(ptr); 34 return asan_free(ptr, &stack); 35 } 36 37 void _free_dbg(void* ptr, int) { 38 free(ptr); 39 } 40 41 void cfree(void *ptr) { 42 CHECK(!"cfree() should not be used on Windows?"); 43 } 44 45 void *malloc(size_t size) { 46 GET_STACK_TRACE_HERE_FOR_MALLOC; 47 return asan_malloc(size, &stack); 48 } 49 50 void* _malloc_dbg(size_t size, int , const char*, int) { 51 return malloc(size); 52 } 53 54 void *calloc(size_t nmemb, size_t size) { 55 GET_STACK_TRACE_HERE_FOR_MALLOC; 56 return asan_calloc(nmemb, size, &stack); 57 } 58 59 void* _calloc_dbg(size_t n, size_t size, int, const char*, int) { 60 return calloc(n, size); 61 } 62 63 void *_calloc_impl(size_t nmemb, size_t size, int *errno_tmp) { 64 return calloc(nmemb, size); 65 } 66 67 void *realloc(void *ptr, size_t size) { 68 GET_STACK_TRACE_HERE_FOR_MALLOC; 69 return asan_realloc(ptr, size, &stack); 70 } 71 72 void *_realloc_dbg(void *ptr, size_t size, int) { 73 CHECK(!"_realloc_dbg should not exist!"); 74 return 0; 75 } 76 77 void* _recalloc(void* p, size_t n, size_t elem_size) { 78 if (!p) 79 return calloc(n, elem_size); 80 const size_t size = n * elem_size; 81 if (elem_size != 0 && size / elem_size != n) 82 return 0; 83 return realloc(p, size); 84 } 85 86 size_t _msize(void *ptr) { 87 GET_STACK_TRACE_HERE_FOR_MALLOC; 88 return asan_malloc_usable_size(ptr, &stack); 89 } 90 91 int _CrtDbgReport(int, const char*, int, 92 const char*, const char*, ...) { 93 ShowStatsAndAbort(); 94 } 95 96 int _CrtDbgReportW(int reportType, const wchar_t*, int, 97 const wchar_t*, const wchar_t*, ...) { 98 ShowStatsAndAbort(); 99 } 100 101 int _CrtSetReportMode(int, int) { 102 return 0; 103 } 104 } // extern "C" 105 106 using __interception::GetRealFunctionAddress; 107 108 // We don't want to include "windows.h" in this file to avoid extra attributes 109 // set on malloc/free etc (e.g. dllimport), so declare a few things manually: 110 extern "C" int __stdcall VirtualProtect(void* addr, size_t size, 111 DWORD prot, DWORD *old_prot); 112 const int PAGE_EXECUTE_READWRITE = 0x40; 113 114 namespace __asan { 115 void ReplaceSystemMalloc() { 116 #if defined(_DLL) 117 # ifdef _WIN64 118 # error ReplaceSystemMalloc was not tested on x64 119 # endif 120 char *crt_malloc; 121 if (GetRealFunctionAddress("malloc", (void**)&crt_malloc)) { 122 // Replace malloc in the CRT dll with a jump to our malloc. 123 DWORD old_prot, unused; 124 CHECK(VirtualProtect(crt_malloc, 16, PAGE_EXECUTE_READWRITE, &old_prot)); 125 REAL(memset)(crt_malloc, 0xCC /* int 3 */, 16); // just in case. 126 127 ptrdiff_t jmp_offset = (char*)malloc - (char*)crt_malloc - 5; 128 crt_malloc[0] = 0xE9; // jmp, should be followed by an offset. 129 REAL(memcpy)(crt_malloc + 1, &jmp_offset, sizeof(jmp_offset)); 130 131 CHECK(VirtualProtect(crt_malloc, 16, old_prot, &unused)); 132 133 // FYI: FlushInstructionCache is needed on Itanium etc but not on x86/x64. 134 } 135 136 // FIXME: investigate whether anything else is needed. 137 #endif 138 } 139 } // namespace __asan 140 141 #endif // _WIN32 142