// https://syzkaller.appspot.com/bug?id=a0a1b089410f757dfbba9c0fa043d99bfe05b2d2 // autogenerated by syzkaller (https://github.com/google/syzkaller) #define _GNU_SOURCE #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 { 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; } #define __syscall syscall 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; int collide = 0; again: 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); 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; } } uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { intptr_t res; switch (call) { case 0: memcpy((void*)0x20000000, "/dev/vmm\000", 9); res = syscall(SYS_openat, 0xffffffffffffff9c, 0x20000000, 0, 0); if (res != -1) r[0] = res; break; case 1: *(uint32_t*)0x200000c0 = 1; *(uint32_t*)0x200000c4 = 0; *(uint64_t*)0x200000c8 = 1; *(uint64_t*)0x200000d0 = 0; *(uint64_t*)0x200000d8 = 0; *(uint64_t*)0x200000e0 = 0; *(uint64_t*)0x200000e8 = 0x40000000000; *(uint64_t*)0x200000f0 = 0x80000000; *(uint64_t*)0x200000f8 = 0; *(uint64_t*)0x20000100 = 0; *(uint64_t*)0x20000108 = 0; *(uint64_t*)0x20000110 = 0; *(uint64_t*)0x20000118 = 0; *(uint64_t*)0x20000120 = 0; *(uint64_t*)0x20000128 = 0; *(uint64_t*)0x20000130 = 0; *(uint64_t*)0x20000138 = 0; *(uint64_t*)0x20000140 = 0; *(uint64_t*)0x20000148 = 0; *(uint64_t*)0x20000150 = 0; *(uint64_t*)0x20000158 = 0; *(uint64_t*)0x20000160 = 0; *(uint64_t*)0x20000168 = 0; *(uint64_t*)0x20000170 = 0; *(uint64_t*)0x20000178 = 0; *(uint64_t*)0x20000180 = 0; *(uint64_t*)0x20000188 = 0; *(uint64_t*)0x20000190 = 0; *(uint64_t*)0x20000198 = 0; *(uint64_t*)0x200001a0 = 0; *(uint64_t*)0x200001a8 = 0; *(uint64_t*)0x200001b0 = 0; *(uint64_t*)0x200001b8 = 0; *(uint64_t*)0x200001c0 = 0; *(uint64_t*)0x200001c8 = 0; *(uint64_t*)0x200001d0 = 0; *(uint64_t*)0x200001d8 = 0; *(uint64_t*)0x200001e0 = 0; *(uint64_t*)0x200001e8 = 0; *(uint64_t*)0x200001f0 = 0; *(uint64_t*)0x200001f8 = 0; *(uint64_t*)0x20000200 = 0; *(uint64_t*)0x20000208 = 0; *(uint64_t*)0x20000210 = 0; *(uint16_t*)0x20000218 = 0; *(uint32_t*)0x2000021c = 0; *(uint32_t*)0x20000220 = 0; *(uint64_t*)0x20000228 = 0; *(uint16_t*)0x20000230 = 0; *(uint32_t*)0x20000234 = 0; *(uint32_t*)0x20000238 = 0; *(uint64_t*)0x20000240 = 0; *(uint16_t*)0x20000248 = 0; *(uint32_t*)0x2000024c = 0; *(uint32_t*)0x20000250 = 0; *(uint64_t*)0x20000258 = 0; *(uint16_t*)0x20000260 = 0; *(uint32_t*)0x20000264 = 0; *(uint32_t*)0x20000268 = 0; *(uint64_t*)0x20000270 = 0; *(uint16_t*)0x20000278 = 0; *(uint32_t*)0x2000027c = 0; *(uint32_t*)0x20000280 = 0; *(uint64_t*)0x20000288 = 0; *(uint16_t*)0x20000290 = 0; *(uint32_t*)0x20000294 = 0; *(uint32_t*)0x20000298 = 0; *(uint64_t*)0x200002a0 = 0; *(uint16_t*)0x200002a8 = 0; *(uint32_t*)0x200002ac = 0; *(uint32_t*)0x200002b0 = 0; *(uint64_t*)0x200002b8 = 0; *(uint16_t*)0x200002c0 = 0; *(uint32_t*)0x200002c4 = 0; *(uint32_t*)0x200002c8 = 0; *(uint64_t*)0x200002d0 = 0; *(uint16_t*)0x200002d8 = 0; *(uint32_t*)0x200002dc = 0; *(uint32_t*)0x200002e0 = 0; *(uint64_t*)0x200002e8 = 0; *(uint16_t*)0x200002f0 = 0; *(uint32_t*)0x200002f4 = 0; *(uint32_t*)0x200002f8 = 0; *(uint64_t*)0x20000300 = 0; syscall(SYS_ioctl, r[0], 0xc5005601, 0x200000c0); break; case 2: memcpy((void*)0x20000080, "/dev/vmm\000", 9); res = syscall(SYS_openat, 0xffffffffffffff9c, 0x20000080, 0x40, 0); if (res != -1) r[1] = res; break; case 3: *(uint64_t*)0x20000490 = 0; syscall(SYS_ioctl, r[1], 0xc0185603, 0x20000480); break; } } int main(void) { syscall(SYS_mmap, 0x20000000, 0x1000000, 3, 0x1012, -1, 0, 0); loop(); return 0; }