// https://syzkaller.appspot.com/bug?id=af3a0728c8cbf6903ec2b0836441287cced00c1c // autogenerated by syzkaller (http://github.com/google/syzkaller) #define _GNU_SOURCE #include #include #include #include #include #include #include #include #include #include #include #include static uintptr_t syz_open_pts(uintptr_t a0, uintptr_t a1) { int ptyno = 0; if (ioctl(a0, TIOCGPTN, &ptyno)) return -1; char buf[128]; sprintf(buf, "/dev/pts/%d", ptyno); return open(buf, a1, 0); } struct thread_t { int created, running, call; pthread_t th; }; static struct thread_t threads[16]; static void execute_call(int call); static int running; static int collide; static void* thr(void* arg) { struct thread_t* th = (struct thread_t*)arg; for (;;) { while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0); execute_call(th->call); __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); } return 0; } static void execute(int num_calls) { int call, thread; running = 0; for (call = 0; call < num_calls; call++) { for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]); thread++) { struct thread_t* th = &threads[thread]; if (!th->created) { th->created = 1; pthread_attr_t attr; pthread_attr_init(&attr); pthread_attr_setstacksize(&attr, 128 << 10); pthread_create(&th->th, &attr, thr, th); } if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) { th->call = call; __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED); __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE); syscall(SYS_futex, &th->running, FUTEX_WAKE); if (collide && call % 2) break; struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (running) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } uint64_t r[5] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; void execute_call(int call) { long res; switch (call) { case 0: res = syscall(__NR_socket, 2, 2, 0); if (res != -1) r[0] = res; break; case 1: res = syscall(__NR_socket, 0x10, 3, 4); if (res != -1) r[1] = res; break; case 2: res = syscall(__NR_socket, 2, 0x80a, 2); if (res != -1) r[2] = res; break; case 3: syscall(__NR_fallocate, r[1], 0, 7, 0xc63); break; case 4: res = syz_open_pts(-1, 2); if (res != -1) r[3] = res; break; case 5: memcpy((void*)0x20000300, "/dev/ptmx", 10); res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000300, 0x100, 0); if (res != -1) r[4] = res; break; case 6: *(uint32_t*)0x20000340 = r[0]; *(uint16_t*)0x20000344 = 0x4000; *(uint16_t*)0x20000346 = 0; *(uint32_t*)0x20000348 = r[1]; *(uint16_t*)0x2000034c = 0x448; *(uint16_t*)0x2000034e = 0; *(uint32_t*)0x20000350 = r[2]; *(uint16_t*)0x20000354 = 0x3100; *(uint16_t*)0x20000356 = 0; *(uint32_t*)0x20000358 = r[3]; *(uint16_t*)0x2000035c = 0x4000; *(uint16_t*)0x2000035e = 0; *(uint32_t*)0x20000360 = r[4]; *(uint16_t*)0x20000364 = 0x410; *(uint16_t*)0x20000366 = 0; syscall(__NR_poll, 0x20000340, 5, 0x8001); break; } } void loop() { execute(7); collide = 1; execute(7); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); loop(); return 0; }