// https://syzkaller.appspot.com/bug?id=66d11d71c4266e16f71ac6a16aba794a1ed75358 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include unsigned long long procid; static __thread int skip_segv; static __thread jmp_buf segv_env; static void segv_handler(int sig, siginfo_t* info, void* ctx) { uintptr_t addr = (uintptr_t)info->si_addr; const uintptr_t prog_start = 1 << 20; const uintptr_t prog_end = 100 << 20; if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) && (addr < prog_start || addr > prog_end)) { _longjmp(segv_env, 1); } exit(sig); } static void install_segv_handler(void) { struct sigaction sa; memset(&sa, 0, sizeof(sa)); sa.sa_sigaction = segv_handler; sa.sa_flags = SA_NODEFER | SA_SIGINFO; sigaction(SIGSEGV, &sa, NULL); sigaction(SIGBUS, &sa, NULL); } #define NONFAILING(...) \ { \ __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \ if (_setjmp(segv_env) == 0) { \ __VA_ARGS__; \ } \ __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \ } static void kill_and_wait(int pid, int* status) { kill(pid, SIGKILL); while (waitpid(-1, status, 0) != pid) { } } static void sleep_ms(uint64_t ms) { usleep(ms * 1000); } static uint64_t current_time_ms(void) { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static void thread_start(void* (*fn)(void*), void* arg) { pthread_t th; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); int i; for (i = 0; i < 100; i++) { if (pthread_create(&th, &attr, fn, arg) == 0) { pthread_attr_destroy(&attr); return; } if (errno == EAGAIN) { usleep(50); continue; } break; } exit(1); } typedef struct { pthread_mutex_t mu; pthread_cond_t cv; int state; } event_t; static void event_init(event_t* ev) { if (pthread_mutex_init(&ev->mu, 0)) exit(1); if (pthread_cond_init(&ev->cv, 0)) exit(1); ev->state = 0; } static void event_reset(event_t* ev) { ev->state = 0; } static void event_set(event_t* ev) { pthread_mutex_lock(&ev->mu); if (ev->state) exit(1); ev->state = 1; pthread_mutex_unlock(&ev->mu); pthread_cond_broadcast(&ev->cv); } static void event_wait(event_t* ev) { pthread_mutex_lock(&ev->mu); while (!ev->state) pthread_cond_wait(&ev->cv, &ev->mu); pthread_mutex_unlock(&ev->mu); } static int event_isset(event_t* ev) { pthread_mutex_lock(&ev->mu); int res = ev->state; pthread_mutex_unlock(&ev->mu); return res; } static int event_timedwait(event_t* ev, uint64_t timeout) { uint64_t start = current_time_ms(); uint64_t now = start; pthread_mutex_lock(&ev->mu); for (;;) { if (ev->state) break; uint64_t remain = timeout - (now - start); struct timespec ts; ts.tv_sec = remain / 1000; ts.tv_nsec = (remain % 1000) * 1000 * 1000; pthread_cond_timedwait(&ev->cv, &ev->mu, &ts); now = current_time_ms(); if (now - start > timeout) break; } int res = ev->state; pthread_mutex_unlock(&ev->mu); return res; } static long syz_execute_func(volatile long text) { volatile long p[8] = {0}; (void)p; asm volatile("" ::"r"(0l), "r"(1l), "r"(2l), "r"(3l), "r"(4l), "r"(5l), "r"(6l), "r"(7l), "r"(8l), "r"(9l), "r"(10l), "r"(11l), "r"(12l), "r"(13l)); NONFAILING(((void (*)(void))(text))()); return 0; } struct thread_t { int created, call; event_t ready, done; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { event_wait(&th->ready); event_reset(&th->ready); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); event_set(&th->done); } return 0; } static void execute_one(void) { int i, call, thread; int collide = 0; again: for (call = 0; call < 6; call++) { for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0])); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; event_init(&th->ready); event_init(&th->done); event_set(&th->done); thread_start(thr, th); } if (!event_isset(&th->done)) continue; event_reset(&th->done); th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); event_set(&th->ready); if (collide && (call % 2) == 0) break; event_timedwait(&th->done, 45); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); if (!collide) { collide = 1; goto again; } } static void execute_one(void); #define WAIT_FLAGS 0 static void loop(void) { int iter; for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) exit(1); if (pid == 0) { execute_one(); exit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break; sleep_ms(1); if (current_time_ms() - start < 5 * 1000) continue; kill_and_wait(pid, &status); break; } } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { long res; switch (call) { case 0: NONFAILING(memcpy( (void*)0x20000000, "\x98\x26\x47\x3e\x43\x1c\x13\x0f\x05\xf3\x0f\x59\xbf\xd9\x13\x00\x00" "\xc4\xa3\x7b\xf0\xc5\x3e\x41\xe2\xe9\xb5\x57\x67\x66\x0f\x6b\x32\xfb" "\x66\x0f\x72\xd5\x0f\x0f\xb8\xc4\x05\x4e\x4e\xed\x75\x1e\x0f\xa0\x45" "\x0f\x0f\xaa\x00\x00\x15\x21\xb7\xab\x34\xd1\xc4\xe1\x0b\xf8\xc4\x70" "\xc4\xc4\x61\xcd\x58\x3d\x00\x00\x00\x81\xc6\x6d\xb7\x12\xfd\x83\x39" "\x7f\xd3\x00\xc9\xdc\xdc\x0f\xbc\xaf\x00\xea\xe8\x00\xf3\x45\xd9\xc6" "\xac\xac\xc4\xc3\x21\x4c\xb9\xa5\x60\x54\x19\xc2\x01\xb0\x0b\x00\x00" "\x00\xf0\x81\x71\xa3\x0b\x8a\x82\x6e\xa8\x0d\xd4\xd4\x8c\xc7\xe8\x62" "\x8f\x68\x08\xa3\x05\x6f\x00\x00\x00\x4e\x00\xc4\x61\x8d\xe3\xc0\xf5" "\x26\x26\x47\x88\xfe\x58\xc4\xa1\xdd\x7d\xbb\xbf\xdd\x5c\xc6\x00\xd0" "\x30\xa1\xc9\xfb\x11\x0f\xd3\xc4\xa2\x61\xb7\xe2", 182)); syz_execute_func(0x20000000); break; case 1: res = syscall(SYS_socket, 0x1c, 1, 0x84); if (res != -1) r[0] = res; break; case 2: NONFAILING(*(uint8_t*)0x20000280 = 0); NONFAILING(*(uint8_t*)0x20000281 = 0); NONFAILING(*(uint8_t*)0x20000282 = 4); NONFAILING(*(uint8_t*)0x20000283 = 7); NONFAILING(*(uint8_t*)0x20000284 = 0xef); NONFAILING(*(uint8_t*)0x20000285 = 0); NONFAILING(*(uint8_t*)0x20000286 = 0x20); NONFAILING(*(uint8_t*)0x20000287 = 7); NONFAILING(*(uint8_t*)0x20000288 = 0x62); NONFAILING(*(uint8_t*)0x20000289 = 4); NONFAILING(*(uint8_t*)0x2000028a = 3); syscall(SYS_setsockopt, r[0], 0x84, 0xc, 0x20000280, 0xb); break; case 3: syscall(SYS_listen, r[0], 0); break; case 4: res = syscall(SYS_fcntl, r[0], 0, r[0]); if (res != -1) r[1] = res; break; case 5: NONFAILING(*(uint32_t*)0x20000000 = 0); syscall(SYS_setsockopt, r[1], 0x84, 0x8008, 0x20000000, 0xffba); break; } } int main(void) { syscall(SYS_mmap, 0x20000000, 0x1000000, 3, 0x1012, -1, 0); install_segv_handler(); for (procid = 0; procid < 4; procid++) { if (fork() == 0) { loop(); } } sleep(1000000); return 0; }