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 #include "interception/interception.h" 21 22 #include <stddef.h> 23 24 // ---------------------- Replacement functions ---------------- {{{1 25 using namespace __asan; // NOLINT 26 27 // FIXME: Simply defining functions with the same signature in *.obj 28 // files overrides the standard functions in *.lib 29 // This works well for simple helloworld-like tests but might need to be 30 // revisited in the future. 31 32 extern "C" { 33 void free(void *ptr) { 34 GET_STACK_TRACE_FREE; 35 return asan_free(ptr, &stack, FROM_MALLOC); 36 } 37 38 void _free_dbg(void* ptr, int) { 39 free(ptr); 40 } 41 42 void cfree(void *ptr) { 43 CHECK(!"cfree() should not be used on Windows?"); 44 } 45 46 void *malloc(size_t size) { 47 GET_STACK_TRACE_MALLOC; 48 return asan_malloc(size, &stack); 49 } 50 51 void* _malloc_dbg(size_t size, int , const char*, int) { 52 return malloc(size); 53 } 54 55 void *calloc(size_t nmemb, size_t size) { 56 GET_STACK_TRACE_MALLOC; 57 return asan_calloc(nmemb, size, &stack); 58 } 59 60 void* _calloc_dbg(size_t n, size_t size, int, const char*, int) { 61 return calloc(n, size); 62 } 63 64 void *_calloc_impl(size_t nmemb, size_t size, int *errno_tmp) { 65 return calloc(nmemb, size); 66 } 67 68 void *realloc(void *ptr, size_t size) { 69 GET_STACK_TRACE_MALLOC; 70 return asan_realloc(ptr, size, &stack); 71 } 72 73 void *_realloc_dbg(void *ptr, size_t size, int) { 74 CHECK(!"_realloc_dbg should not exist!"); 75 return 0; 76 } 77 78 void* _recalloc(void* p, size_t n, size_t elem_size) { 79 if (!p) 80 return calloc(n, elem_size); 81 const size_t size = n * elem_size; 82 if (elem_size != 0 && size / elem_size != n) 83 return 0; 84 return realloc(p, size); 85 } 86 87 size_t _msize(void *ptr) { 88 GET_STACK_TRACE_MALLOC; 89 return asan_malloc_usable_size(ptr, &stack); 90 } 91 92 int _CrtDbgReport(int, const char*, int, 93 const char*, const char*, ...) { 94 ShowStatsAndAbort(); 95 } 96 97 int _CrtDbgReportW(int reportType, const wchar_t*, int, 98 const wchar_t*, const wchar_t*, ...) { 99 ShowStatsAndAbort(); 100 } 101 102 int _CrtSetReportMode(int, int) { 103 return 0; 104 } 105 } // extern "C" 106 107 using __interception::GetRealFunctionAddress; 108 109 // We don't want to include "windows.h" in this file to avoid extra attributes 110 // set on malloc/free etc (e.g. dllimport), so declare a few things manually: 111 extern "C" int __stdcall VirtualProtect(void* addr, size_t size, 112 DWORD prot, DWORD *old_prot); 113 const int PAGE_EXECUTE_READWRITE = 0x40; 114 115 namespace __asan { 116 void ReplaceSystemMalloc() { 117 #if defined(_DLL) 118 # ifdef _WIN64 119 # error ReplaceSystemMalloc was not tested on x64 120 # endif 121 char *crt_malloc; 122 if (GetRealFunctionAddress("malloc", (void**)&crt_malloc)) { 123 // Replace malloc in the CRT dll with a jump to our malloc. 124 DWORD old_prot, unused; 125 CHECK(VirtualProtect(crt_malloc, 16, PAGE_EXECUTE_READWRITE, &old_prot)); 126 REAL(memset)(crt_malloc, 0xCC /* int 3 */, 16); // just in case. 127 128 ptrdiff_t jmp_offset = (char*)malloc - (char*)crt_malloc - 5; 129 crt_malloc[0] = 0xE9; // jmp, should be followed by an offset. 130 REAL(memcpy)(crt_malloc + 1, &jmp_offset, sizeof(jmp_offset)); 131 132 CHECK(VirtualProtect(crt_malloc, 16, old_prot, &unused)); 133 134 // FYI: FlushInstructionCache is needed on Itanium etc but not on x86/x64. 135 } 136 137 // FIXME: investigate whether anything else is needed. 138 #endif 139 } 140 } // namespace __asan 141 142 #endif // _WIN32 143