mozalloc_abort.cpp (3322B)
1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- 2 * vim: sw=2 ts=4 et : 3 */ 4 /* This Source Code Form is subject to the terms of the Mozilla Public 5 * License, v. 2.0. If a copy of the MPL was not distributed with this 6 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ 7 8 #include "mozilla/mozalloc_abort.h" 9 10 #ifdef ANDROID 11 # include <android/log.h> 12 #endif 13 #ifdef MOZ_WIDGET_ANDROID 14 # include "APKOpen.h" 15 # include "dlfcn.h" 16 #endif 17 #include <stdio.h> 18 #include <string.h> 19 20 #include "mozilla/Assertions.h" 21 #include "mozilla/Sprintf.h" 22 23 void mozalloc_abort(const char* const msg) { 24 #ifndef ANDROID 25 fputs(msg, stderr); 26 fputs("\n", stderr); 27 #else 28 __android_log_print(ANDROID_LOG_ERROR, "Gecko", "mozalloc_abort: %s", msg); 29 #endif 30 31 #ifdef MOZ_WIDGET_ANDROID 32 abortThroughJava(msg); 33 #endif 34 35 MOZ_CRASH_UNSAFE(msg); 36 } 37 38 #ifdef MOZ_WIDGET_ANDROID 39 template <size_t N> 40 void fillAbortMessage(char (&msg)[N], uintptr_t retAddress) { 41 /* 42 * On Android, we often don't have reliable backtrace when crashing inside 43 * abort(). Therefore, we try to find out who is calling abort() and add 44 * that to the message. 45 */ 46 Dl_info info = {}; 47 dladdr(reinterpret_cast<void*>(retAddress), &info); 48 49 const char* const module = info.dli_fname ? info.dli_fname : ""; 50 const char* const base_module = strrchr(module, '/'); 51 const void* const module_offset = 52 reinterpret_cast<void*>(retAddress - uintptr_t(info.dli_fbase)); 53 const char* const sym = info.dli_sname ? info.dli_sname : ""; 54 55 SprintfLiteral(msg, "abort() called from %s:%p (%s)", 56 base_module ? base_module + 1 : module, module_offset, sym); 57 } 58 #endif 59 60 #if defined(XP_UNIX) && !defined(MOZ_ASAN) && !defined(MOZ_TSAN) && \ 61 !defined(MOZ_UBSAN) && !defined(LIBFUZZER) && !defined(AFLFUZZ) && \ 62 !defined(FUZZING_JS_FUZZILLI) 63 // Define abort() here, so that it is used instead of the system abort(). This 64 // lets us control the behavior when aborting, in order to get better results 65 // on *NIX platforms. See mozalloc_abort for details. 66 // 67 // For AddressSanitizer, we must not redefine system abort because the ASan 68 // option "abort_on_error=1" calls abort() and therefore causes the following 69 // call chain with our redefined abort: 70 // 71 // ASan -> abort() -> moz_abort() -> MOZ_CRASH() -> Segmentation fault 72 // 73 // That segmentation fault will be interpreted as another bug by ASan and as a 74 // result, ASan will just exit(1) instead of aborting. 75 // 76 // The same applies to ThreadSanitizer when run with "halt_on_error=1" in 77 // combination with "abort_on_error=1". 78 // 79 // When building for fuzzing without ASan or TSan, we automatically pull in the 80 // UndefinedBehaviorSanitizer runtime which also requires the same workaround 81 // as with ASan or TSan. 82 extern "C" void abort(void) { 83 # ifdef MOZ_WIDGET_ANDROID 84 char msg[64] = {}; 85 fillAbortMessage(msg, uintptr_t(__builtin_return_address(0))); 86 # else 87 const char* const msg = "Redirecting call to abort() to mozalloc_abort\n"; 88 # endif 89 90 mozalloc_abort(msg); 91 92 // We won't reach here because mozalloc_abort() is [[noreturn]]. But that 93 // annotation isn't used on ARM (see mozalloc_abort.h for why) so we add a 94 // unreachable marker here to avoid a "'noreturn' function does return" 95 // warning. 96 MOZ_ASSUME_UNREACHABLE_MARKER(); 97 } 98 #endif