// https://syzkaller.appspot.com/bug?id=8b01a793ad9f9a3a575189a2bdea572c55fe86d7 // 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 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, 1000000); } 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_ACQUIRE)) return 1; now = current_time_ms(); if (now - start > timeout) return 0; } } static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2) { if (a0 == 0xc || a0 == 0xb) { char buf[128]; sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1, (uint8_t)a2); return open(buf, O_RDWR, 0); } else { char buf[1024]; char* hash; strncpy(buf, (char*)a0, sizeof(buf) - 1); buf[sizeof(buf) - 1] = 0; while ((hash = strchr(buf, '#'))) { *hash = '0' + (char)(a1 % 10); a1 /= 10; } return open(buf, a2, 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 loop(void) { int i, call, thread; for (call = 0; call < 4; 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 = 0; switch (call) { case 0: memcpy((void*)0x20000180, "/dev/fb0\000", 9); res = syscall(__NR_openat, 0xffffffffffffff9cul, 0x20000180ul, 0ul, 0ul); if (res != -1) r[0] = res; break; case 1: *(uint32_t*)0x20000000 = 0; *(uint32_t*)0x20000004 = 0; *(uint32_t*)0x20000008 = 0; *(uint32_t*)0x2000000c = 0; *(uint32_t*)0x20000010 = 0; *(uint32_t*)0x20000014 = 0; *(uint32_t*)0x20000018 = 8; *(uint32_t*)0x2000001c = 0; *(uint32_t*)0x20000020 = 0; *(uint32_t*)0x20000024 = 0; *(uint32_t*)0x20000028 = 0; *(uint32_t*)0x2000002c = 0; *(uint32_t*)0x20000030 = 0x20; *(uint32_t*)0x20000034 = 0; *(uint32_t*)0x20000038 = 0; *(uint32_t*)0x2000003c = 0; *(uint32_t*)0x20000040 = 0; *(uint32_t*)0x20000044 = 0; *(uint32_t*)0x20000048 = 0; *(uint32_t*)0x2000004c = 0; *(uint32_t*)0x20000050 = 0; *(uint32_t*)0x20000054 = 0x43; *(uint32_t*)0x20000058 = 0; *(uint32_t*)0x2000005c = 0; *(uint32_t*)0x20000060 = 0; *(uint32_t*)0x20000064 = 0; *(uint32_t*)0x20000068 = 0; *(uint32_t*)0x2000006c = 0; *(uint32_t*)0x20000070 = 0; *(uint32_t*)0x20000074 = 0; *(uint32_t*)0x20000078 = 0; *(uint32_t*)0x2000007c = 0; *(uint32_t*)0x20000080 = 0; *(uint32_t*)0x20000084 = 0; *(uint32_t*)0x20000088 = 0; *(uint32_t*)0x2000008c = 0; *(uint32_t*)0x20000090 = 0; *(uint32_t*)0x20000094 = 0; *(uint32_t*)0x20000098 = 0; *(uint32_t*)0x2000009c = 0; syscall(__NR_ioctl, r[0], 0x4601, 0x20000000ul); break; case 2: res = syz_open_dev(0xc, 4, 0x15); if (res != -1) r[1] = res; break; case 3: *(uint8_t*)0x200000c0 = 3; *(uint8_t*)0x200000c1 = 2; *(uint16_t*)0x200000c2 = 0; *(uint16_t*)0x200000c4 = 0; *(uint16_t*)0x200000c6 = 0; *(uint16_t*)0x200000c8 = 0; *(uint16_t*)0x200000ca = 0; syscall(__NR_ioctl, r[1], 0x5412, 0x200000c0ul); break; } } int main(void) { syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul); syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul); loop(); return 0; }