| /* |
| * Copyright 2006, The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #define LOG_TAG "crasher" |
| |
| #include <assert.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <pthread.h> |
| #include <sched.h> |
| #include <signal.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <sys/cdefs.h> |
| #include <sys/mman.h> |
| #include <sys/ptrace.h> |
| #include <sys/socket.h> |
| #include <sys/wait.h> |
| #include <unistd.h> |
| |
| #include <android/log.h> |
| #include <cutils/sockets.h> |
| |
| #if defined(STATIC_CRASHER) |
| #include "debuggerd/client.h" |
| #endif |
| |
| #ifndef __unused |
| #define __unused __attribute__((__unused__)) |
| #endif |
| |
| extern const char* __progname; |
| |
| extern "C" void crash1(void); |
| extern "C" void crashnostack(void); |
| |
| static int do_action(const char* arg); |
| |
| static void maybe_abort() { |
| if (time(0) != 42) { |
| abort(); |
| } |
| } |
| |
| static char* smash_stack_dummy_buf; |
| __attribute__ ((noinline)) static void smash_stack_dummy_function(volatile int* plen) { |
| smash_stack_dummy_buf[*plen] = 0; |
| } |
| |
| // This must be marked with "__attribute__ ((noinline))", to ensure the |
| // compiler generates the proper stack guards around this function. |
| // Assign local array address to global variable to force stack guards. |
| // Use another noinline function to corrupt the stack. |
| __attribute__ ((noinline)) static int smash_stack(volatile int* plen) { |
| printf("%s: deliberately corrupting stack...\n", __progname); |
| |
| char buf[128]; |
| smash_stack_dummy_buf = buf; |
| // This should corrupt stack guards and make process abort. |
| smash_stack_dummy_function(plen); |
| return 0; |
| } |
| |
| #if defined(__clang__) |
| #pragma clang diagnostic push |
| #pragma clang diagnostic ignored "-Winfinite-recursion" |
| #endif |
| |
| static void* global = 0; // So GCC doesn't optimize the tail recursion out of overflow_stack. |
| |
| __attribute__((noinline)) static void overflow_stack(void* p) { |
| void* buf[1]; |
| buf[0] = p; |
| global = buf; |
| overflow_stack(&buf); |
| } |
| |
| #if defined(__clang__) |
| #pragma clang diagnostic pop |
| #endif |
| |
| static void *noisy(void *x) |
| { |
| char c = (uintptr_t) x; |
| for(;;) { |
| usleep(250*1000); |
| write(2, &c, 1); |
| if(c == 'C') *((volatile unsigned*) 0) = 42; |
| } |
| return NULL; |
| } |
| |
| static int ctest() |
| { |
| pthread_t thr; |
| pthread_attr_t attr; |
| pthread_attr_init(&attr); |
| pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); |
| pthread_create(&thr, &attr, noisy, (void*) 'A'); |
| pthread_create(&thr, &attr, noisy, (void*) 'B'); |
| pthread_create(&thr, &attr, noisy, (void*) 'C'); |
| for(;;) ; |
| return 0; |
| } |
| |
| static void* thread_callback(void* raw_arg) |
| { |
| return (void*) (uintptr_t) do_action((const char*) raw_arg); |
| } |
| |
| static int do_action_on_thread(const char* arg) |
| { |
| pthread_t t; |
| pthread_create(&t, NULL, thread_callback, (void*) arg); |
| void* result = NULL; |
| pthread_join(t, &result); |
| return (int) (uintptr_t) result; |
| } |
| |
| __attribute__((noinline)) static int crash3(int a) { |
| *((int*) 0xdead) = a; |
| return a*4; |
| } |
| |
| __attribute__((noinline)) static int crash2(int a) { |
| a = crash3(a) + 2; |
| return a*3; |
| } |
| |
| __attribute__((noinline)) static int crash(int a) { |
| a = crash2(a) + 1; |
| return a*2; |
| } |
| |
| static void abuse_heap() { |
| char buf[16]; |
| free((void*) buf); // GCC is smart enough to warn about this, but we're doing it deliberately. |
| } |
| |
| static void sigsegv_non_null() { |
| int* a = (int *)(&do_action); |
| *a = 42; |
| } |
| |
| static int do_action(const char* arg) |
| { |
| fprintf(stderr, "%s: init pid=%d tid=%d\n", __progname, getpid(), gettid()); |
| |
| if (!strncmp(arg, "wait-", strlen("wait-"))) { |
| char buf[1]; |
| TEMP_FAILURE_RETRY(read(STDIN_FILENO, buf, sizeof(buf))); |
| return do_action(arg + strlen("wait-")); |
| } else if (!strncmp(arg, "exhaustfd-", strlen("exhaustfd-"))) { |
| errno = 0; |
| while (errno != EMFILE) { |
| open("/dev/null", O_RDONLY); |
| } |
| return do_action(arg + strlen("exhaustfd-")); |
| } else if (!strncmp(arg, "thread-", strlen("thread-"))) { |
| return do_action_on_thread(arg + strlen("thread-")); |
| } else if (!strcmp(arg, "SIGSEGV-non-null")) { |
| sigsegv_non_null(); |
| } else if (!strcmp(arg, "smash-stack")) { |
| volatile int len = 128; |
| return smash_stack(&len); |
| } else if (!strcmp(arg, "stack-overflow")) { |
| overflow_stack(NULL); |
| } else if (!strcmp(arg, "nostack")) { |
| crashnostack(); |
| } else if (!strcmp(arg, "ctest")) { |
| return ctest(); |
| } else if (!strcmp(arg, "exit")) { |
| exit(1); |
| } else if (!strcmp(arg, "crash") || !strcmp(arg, "SIGSEGV")) { |
| return crash(42); |
| } else if (!strcmp(arg, "abort")) { |
| maybe_abort(); |
| } else if (!strcmp(arg, "assert")) { |
| __assert("some_file.c", 123, "false"); |
| } else if (!strcmp(arg, "assert2")) { |
| __assert2("some_file.c", 123, "some_function", "false"); |
| } else if (!strcmp(arg, "fortify")) { |
| char buf[10]; |
| __read_chk(-1, buf, 32, 10); |
| while (true) pause(); |
| } else if (!strcmp(arg, "LOG_ALWAYS_FATAL")) { |
| LOG_ALWAYS_FATAL("hello %s", "world"); |
| } else if (!strcmp(arg, "LOG_ALWAYS_FATAL_IF")) { |
| LOG_ALWAYS_FATAL_IF(true, "hello %s", "world"); |
| } else if (!strcmp(arg, "SIGFPE")) { |
| raise(SIGFPE); |
| return EXIT_SUCCESS; |
| } else if (!strcmp(arg, "SIGTRAP")) { |
| raise(SIGTRAP); |
| return EXIT_SUCCESS; |
| } else if (!strcmp(arg, "heap-usage")) { |
| abuse_heap(); |
| } else if (!strcmp(arg, "SIGSEGV-unmapped")) { |
| char* map = reinterpret_cast<char*>(mmap(NULL, sizeof(int), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0)); |
| munmap(map, sizeof(int)); |
| map[0] = '8'; |
| } |
| |
| fprintf(stderr, "%s OP\n", __progname); |
| fprintf(stderr, "where OP is:\n"); |
| fprintf(stderr, " smash-stack overwrite a stack-guard canary\n"); |
| fprintf(stderr, " stack-overflow recurse until the stack overflows\n"); |
| fprintf(stderr, " heap-corruption cause a libc abort by corrupting the heap\n"); |
| fprintf(stderr, " heap-usage cause a libc abort by abusing a heap function\n"); |
| fprintf(stderr, " nostack crash with a NULL stack pointer\n"); |
| fprintf(stderr, " ctest (obsoleted by thread-crash?)\n"); |
| fprintf(stderr, " exit call exit(1)\n"); |
| fprintf(stderr, " abort call abort()\n"); |
| fprintf(stderr, " assert call assert() without a function\n"); |
| fprintf(stderr, " assert2 call assert() with a function\n"); |
| fprintf(stderr, " fortify fail a _FORTIFY_SOURCE check\n"); |
| fprintf(stderr, " LOG_ALWAYS_FATAL call LOG_ALWAYS_FATAL\n"); |
| fprintf(stderr, " LOG_ALWAYS_FATAL_IF call LOG_ALWAYS_FATAL\n"); |
| fprintf(stderr, " SIGFPE cause a SIGFPE\n"); |
| fprintf(stderr, " SIGSEGV cause a SIGSEGV at address 0x0 (synonym: crash)\n"); |
| fprintf(stderr, " SIGSEGV-non-null cause a SIGSEGV at a non-zero address\n"); |
| fprintf(stderr, " SIGSEGV-unmapped mmap/munmap a region of memory and then attempt to access it\n"); |
| fprintf(stderr, " SIGTRAP cause a SIGTRAP\n"); |
| fprintf(stderr, "prefix any of the above with 'thread-' to not run\n"); |
| fprintf(stderr, "on the process' main thread.\n"); |
| fprintf(stderr, "prefix any of the above with 'exhaustfd-' to exhaust\n"); |
| fprintf(stderr, "all available file descriptors before crashing.\n"); |
| fprintf(stderr, "prefix any of the above with 'wait-' to wait until input is received on stdin\n"); |
| |
| return EXIT_SUCCESS; |
| } |
| |
| int main(int argc, char **argv) |
| { |
| fprintf(stderr, "%s: built at " __TIME__ "!@\n", __progname); |
| |
| #if defined(STATIC_CRASHER) |
| debuggerd_callbacks_t callbacks = { |
| .get_abort_message = []() { |
| static struct { |
| size_t size; |
| char msg[32]; |
| } msg; |
| |
| msg.size = strlen("dummy abort message"); |
| memcpy(msg.msg, "dummy abort message", strlen("dummy abort message")); |
| return reinterpret_cast<abort_msg_t*>(&msg); |
| }, |
| .post_dump = nullptr |
| }; |
| debuggerd_init(&callbacks); |
| #endif |
| |
| if (argc > 1) { |
| return do_action(argv[1]); |
| } else { |
| crash1(); |
| } |
| |
| return 0; |
| } |