| //===-- asan_win_uar_thunk.cc ---------------------------------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file is a part of AddressSanitizer, an address sanity checker. |
| // |
| // This file defines things that need to be present in the application modules |
| // to interact with the ASan DLL runtime correctly and can't be implemented |
| // using the default "import library" generated when linking the DLL RTL. |
| // |
| // This includes: |
| // - forwarding the detect_stack_use_after_return runtime option |
| // - installing a custom SEH handler |
| // |
| //===----------------------------------------------------------------------===// |
| |
| // Only compile this code when buidling asan_dynamic_runtime_thunk.lib |
| // Using #ifdef rather than relying on Makefiles etc. |
| // simplifies the build procedure. |
| #ifdef ASAN_DYNAMIC_RUNTIME_THUNK |
| #include <windows.h> |
| #include <psapi.h> |
| |
| extern "C" { |
| //////////////////////////////////////////////////////////////////////////////// |
| // Define a copy of __asan_option_detect_stack_use_after_return that should be |
| // used when linking an MD runtime with a set of object files on Windows. |
| // |
| // The ASan MD runtime dllexports '__asan_option_detect_stack_use_after_return', |
| // so normally we would just dllimport it. Unfortunately, the dllimport |
| // attribute adds __imp_ prefix to the symbol name of a variable. |
| // Since in general we don't know if a given TU is going to be used |
| // with a MT or MD runtime and we don't want to use ugly __imp_ names on Windows |
| // just to work around this issue, let's clone the a variable that is |
| // constant after initialization anyways. |
| __declspec(dllimport) int __asan_should_detect_stack_use_after_return(); |
| int __asan_option_detect_stack_use_after_return = |
| __asan_should_detect_stack_use_after_return(); |
| } |
| |
| //////////////////////////////////////////////////////////////////////////////// |
| // For some reason, the MD CRT doesn't call the C/C++ terminators as MT does. |
| // To work around this, for each DLL we schedule a call to |
| // UnregisterGlobalsInRange atexit() specifying the address range of the DLL |
| // image to unregister globals in that range. We don't do the same |
| // for the main module (.exe) as the asan_globals.cc allocator is destroyed |
| // by the time UnregisterGlobalsInRange is executed. |
| // See PR22545 for the details. |
| namespace __asan { |
| __declspec(dllimport) |
| void UnregisterGlobalsInRange(void *beg, void *end); |
| } |
| |
| namespace { |
| void *this_module_base, *this_module_end; |
| |
| void UnregisterGlobals() { |
| __asan::UnregisterGlobalsInRange(this_module_base, this_module_end); |
| } |
| |
| int ScheduleUnregisterGlobals() { |
| HMODULE this_module = 0; |
| // Increments the reference counter of the DLL module, so need to call |
| // FreeLibrary later. |
| if (!GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS, |
| (LPCTSTR)&UnregisterGlobals, &this_module)) |
| return 1; |
| |
| // Skip the main module. |
| if (this_module == GetModuleHandle(0)) |
| return 0; |
| |
| MODULEINFO mi; |
| bool success = |
| GetModuleInformation(GetCurrentProcess(), this_module, &mi, sizeof(mi)); |
| if (!FreeLibrary(this_module)) |
| return 2; |
| if (!success) |
| return 3; |
| |
| this_module_base = mi.lpBaseOfDll; |
| this_module_end = (char*)mi.lpBaseOfDll + mi.SizeOfImage; |
| |
| return atexit(UnregisterGlobals); |
| } |
| } // namespace |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // ASan SEH handling. |
| extern "C" __declspec(dllimport) int __asan_set_seh_filter(); |
| static int SetSEHFilter() { return __asan_set_seh_filter(); } |
| |
| /////////////////////////////////////////////////////////////////////////////// |
| // We schedule some work at start-up by placing callbacks to our code to the |
| // list of CRT C initializers. |
| // |
| // First, declare sections we'll be using: |
| #pragma section(".CRT$XID", long, read) // NOLINT |
| #pragma section(".CRT$XIZ", long, read) // NOLINT |
| |
| // We need to call 'atexit(UnregisterGlobals);' after atexit() is initialized |
| // (.CRT$XIC) but before the C++ constructors (.CRT$XCA). |
| __declspec(allocate(".CRT$XID")) |
| static int (*__asan_schedule_unregister_globals)() = ScheduleUnregisterGlobals; |
| |
| // We need to set the ASan-specific SEH handler at the end of CRT initialization |
| // of each module (see also asan_win.cc). |
| // |
| // Unfortunately, putting a pointer to __asan_set_seh_filter into |
| // __asan_intercept_seh gets optimized out, so we have to use an extra function. |
| extern "C" __declspec(allocate(".CRT$XIZ")) |
| int (*__asan_seh_interceptor)() = SetSEHFilter; |
| |
| #endif // ASAN_DYNAMIC_RUNTIME_THUNK |