// https://syzkaller.appspot.com/bug?id=2ba02045eb5dbeb12c20b68c462f4866fed8c949 // 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 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 { int state; } event_t; static void event_init(event_t* ev) { ev->state = 0; } static void event_reset(event_t* ev) { ev->state = 0; } static void event_set(event_t* ev) { if (ev->state) exit(1); __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG); } static void event_wait(event_t* ev) { while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0); } static int event_isset(event_t* ev) { return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE); } static int event_timedwait(event_t* ev, uint64_t timeout) { uint64_t start = current_time_ms(); uint64_t now = start; for (;;) { uint64_t remain = timeout - (now - start); struct timespec ts; ts.tv_sec = remain / 1000; ts.tv_nsec = (remain % 1000) * 1000 * 1000; syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts); if (__atomic_load_n(&ev->state, __ATOMIC_RELAXED)) return 1; now = current_time_ms(); if (now - start > timeout) return 0; } } static bool write_file(const char* file, const char* what, ...) { char buf[1024]; va_list args; va_start(args, what); vsnprintf(buf, sizeof(buf), what, args); va_end(args); buf[sizeof(buf) - 1] = 0; int len = strlen(buf); int fd = open(file, O_WRONLY | O_CLOEXEC); if (fd == -1) return false; if (write(fd, buf, len) != len) { int err = errno; close(fd); errno = err; return false; } close(fd); return true; } static int inject_fault(int nth) { int fd; fd = open("/proc/thread-self/fail-nth", O_RDWR); if (fd == -1) exit(1); char buf[16]; sprintf(buf, "%d", nth + 1); if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) exit(1); return fd; } static void setup_fault() { static struct { const char* file; const char* val; bool fatal; } files[] = { {"/sys/kernel/debug/failslab/ignore-gfp-wait", "N", true}, {"/sys/kernel/debug/fail_futex/ignore-private", "N", false}, {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem", "N", false}, {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait", "N", false}, {"/sys/kernel/debug/fail_page_alloc/min-order", "0", false}, }; unsigned i; for (i = 0; i < sizeof(files) / sizeof(files[0]); i++) { if (!write_file(files[i].file, files[i].val)) { if (files[i].fatal) exit(1); } } } 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 loop(void) { int i, call, thread; for (call = 0; call < 9; 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); event_timedwait(&th->done, 45); break; } } for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++) sleep_ms(1); } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res; switch (call) { case 0: res = syscall(__NR_socket, 0xa, 1, 0); if (res != -1) r[0] = res; break; case 1: *(uint32_t*)0x20000000 = 1; syscall(__NR_setsockopt, r[0], 6, 0x13, 0x20000000, 4); break; case 2: *(uint16_t*)0x20000140 = 0xa; *(uint16_t*)0x20000142 = htobe16(0); *(uint32_t*)0x20000144 = htobe32(0); memcpy((void*)0x20000148, "\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000", 16); *(uint32_t*)0x20000158 = 0; syscall(__NR_connect, r[0], 0x20000140, 0x1c); break; case 3: res = syscall(__NR_socket, 2, 2, 0x88); if (res != -1) r[1] = res; break; case 4: syscall(__NR_ioctl, r[1], 0x1000008912, 0); break; case 5: memcpy((void*)0x20000540, "tls\000", 4); syscall(__NR_setsockopt, r[0], 6, 0x1f, 0x20000540, 0xf8); break; case 6: syscall(__NR_mmap, 0x20003000, 0xffc000, 0xfffffffffffffffc, 0x32, -1, 0); break; case 7: *(uint16_t*)0x200000c0 = 0x303; *(uint16_t*)0x200000c2 = 0x33; memcpy((void*)0x200000c4, "\xfd\xf6\x6b\x92\x0a\x23\x9d\xbb", 8); memcpy((void*)0x200000cc, "\xfa\x01\x72\xd0\x8d\x5d\xf0\x48\x1b\x90\xd7\xda\xad\xa8\x02\xea", 16); memcpy((void*)0x200000dc, "\x7d\x28\x89\x16", 4); memcpy((void*)0x200000e0, "\x35\xf9\xfa\x48\xe9\xdc\x00\xf2", 8); syscall(__NR_setsockopt, r[0], 0x11a, 1, 0x200000c0, 0x28); break; case 8: inject_fault(2); syscall(__NR_sendto, r[0], 0x200005c0, 0xfffffece, 0, 0, 0); break; } } int main(void) { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); setup_fault(); loop(); return 0; }