// https://syzkaller.appspot.com/bug?id=5d69fe236df10929f73c429850eefee7a645d158 // 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 #include 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 void sandbox_common() { if (setsid() == -1) exit(1); struct rlimit rlim; rlim.rlim_cur = rlim.rlim_max = 8 << 20; setrlimit(RLIMIT_MEMLOCK, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_FSIZE, &rlim); rlim.rlim_cur = rlim.rlim_max = 1 << 20; setrlimit(RLIMIT_STACK, &rlim); rlim.rlim_cur = rlim.rlim_max = 0; setrlimit(RLIMIT_CORE, &rlim); rlim.rlim_cur = rlim.rlim_max = 256; setrlimit(RLIMIT_NOFILE, &rlim); } static void loop(); static int do_sandbox_none(void) { sandbox_common(); loop(); 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 < 16; 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; } } } #ifndef SYS_connect #define SYS_connect 98 #endif #ifndef SYS_dup #define SYS_dup 41 #endif #ifndef SYS_fcntl #define SYS_fcntl 92 #endif #ifndef SYS_getsockname #define SYS_getsockname 32 #endif #ifndef SYS_getsockopt #define SYS_getsockopt 118 #endif #ifndef SYS_mmap #define SYS_mmap 197 #endif #ifndef SYS_openat #define SYS_openat 468 #endif #ifndef SYS_preadv #define SYS_preadv 289 #endif #ifndef SYS_sendto #define SYS_sendto 133 #endif #ifndef SYS_setitimer #define SYS_setitimer 425 #endif #ifndef SYS_socket #define SYS_socket 394 #endif #ifndef SYS_socketpair #define SYS_socketpair 135 #endif #ifndef SYS_stat #define SYS_stat 439 #endif uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { long res; switch (call) { case 0: res = syscall(SYS_dup, 0xffffff9c); if (res != -1) r[0] = res; break; case 1: NONFAILING(*(uint32_t*)0x20000040 = 0x10); syscall(SYS_getsockopt, r[0], 0xffff, 0x100c, 0x20000000, 0x20000040); break; case 2: NONFAILING(*(uint32_t*)0x200000c0 = 0xc); syscall(SYS_getsockname, r[0], 0x20000080, 0x200000c0); break; case 3: NONFAILING(*(uint32_t*)0x20000200 = 0xc); syscall(SYS_getsockname, r[0], 0x200001c0, 0x20000200); break; case 4: NONFAILING(memcpy((void*)0x20000280, "./file0/file0\000", 14)); syscall(SYS_stat, 0x20000280, 0x200002c0); break; case 5: res = syscall(SYS_socketpair, 1, 2, 0, 0x200003c0); if (res != -1) { NONFAILING(r[1] = *(uint32_t*)0x200003c0); NONFAILING(r[2] = *(uint32_t*)0x200003c4); } break; case 6: NONFAILING(*(uint16_t*)0x20000400 = 2); NONFAILING(*(uint16_t*)0x20000402 = htobe16(0x4e20)); NONFAILING(*(uint8_t*)0x20000404 = 0); NONFAILING(*(uint8_t*)0x20000405 = 0); NONFAILING(*(uint8_t*)0x20000406 = 0); NONFAILING(*(uint8_t*)0x20000407 = 0); NONFAILING(*(uint8_t*)0x20000408 = 0); NONFAILING(*(uint8_t*)0x20000409 = 0); NONFAILING(*(uint8_t*)0x2000040a = 0); NONFAILING(*(uint8_t*)0x2000040b = 0); syscall(SYS_connect, r[0], 0x20000400, 0xc); break; case 7: NONFAILING(*(uint64_t*)0x20000580 = 0x20000440); NONFAILING(*(uint64_t*)0x20000588 = 0xb3); NONFAILING(*(uint64_t*)0x20000590 = 0); NONFAILING(*(uint64_t*)0x20000598 = 0); syscall(SYS_preadv, r[2], 0x20000580, 2, 0); break; case 8: syscall(SYS_getsockopt, r[2], 0xffff, 0x11, 0x200005c0, 0xc); break; case 9: NONFAILING(*(uint64_t*)0x200006c0 = 0x490c575); NONFAILING(*(uint64_t*)0x200006c8 = 0); NONFAILING(*(uint64_t*)0x200006d0 = 0); NONFAILING(*(uint64_t*)0x200006d8 = 3); syscall(SYS_setitimer, 0, 0x200006c0, 0x20000700); break; case 10: NONFAILING(memcpy((void*)0x20000740, "./file0/file0/file0\000", 20)); syscall(SYS_openat, r[0], 0x20000740, 0x1000100, 4); break; case 11: NONFAILING(*(uint32_t*)0x20000880 = 0x81); syscall(SYS_getsockopt, r[0], 0, 1, 0x200007c0, 0x20000880); break; case 12: syscall(SYS_socket, 2, 0x20000007, 1); break; case 13: syscall(SYS_sendto, r[1], 0x200019c0, 0, 0xa, 0, 0); break; case 14: syscall(SYS_fcntl, r[2], 4, 0x10000); break; case 15: syscall(SYS_fcntl, r[1], 1, 0); break; } } int main(void) { syscall(SYS_mmap, 0x20000000, 0x1000000, 3, 0x1012, -1, 0, 0); install_segv_handler(); do_sandbox_none(); return 0; }