// https://syzkaller.appspot.com/bug?id=aec313f3f7ebc2ee0abb1104a3631ab8fd1e90f2 // autogenerated by syzkaller (http://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 __attribute__((noreturn)) static void doexit(int status) { volatile unsigned i; syscall(__NR_exit_group, status); for (i = 0;; i++) { } } #include #include #include #include #include const int kFailStatus = 67; const int kRetryStatus = 69; static void fail(const char* msg, ...) { int e = errno; va_list args; va_start(args, msg); vfprintf(stderr, msg, args); va_end(args); fprintf(stderr, " (errno %d)\n", e); doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus); } static uint64_t current_time_ms() { struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts)) fail("clock_gettime failed"); return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000; } static uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t 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); } } static void execute_one(); extern unsigned long long procid; static void loop() { int iter; for (iter = 0;; iter++) { int pid = fork(); if (pid < 0) fail("clone failed"); if (pid == 0) { prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); execute_one(); doexit(0); } int status = 0; uint64_t start = current_time_ms(); for (;;) { int res = waitpid(-1, &status, __WALL | WNOHANG); if (res == pid) { break; } usleep(1000); if (current_time_ms() - start < 3 * 1000) continue; kill(-pid, SIGKILL); kill(pid, SIGKILL); while (waitpid(-1, &status, __WALL) != pid) { } break; } } } 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[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; unsigned long long procid; void execute_call(int call) { long res; switch (call) { case 0: memcpy((void*)0x20000000, "/dev/kvm", 9); res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000000, 0, 0); if (res != -1) r[0] = res; break; case 1: res = syscall(__NR_ioctl, r[0], 0xae01, 0); if (res != -1) r[1] = res; break; case 2: res = syscall(__NR_eventfd, 0); if (res != -1) r[2] = res; break; case 3: syscall(__NR_ioctl, r[0], 0xae03, 0); break; case 4: memcpy((void*)0x200000c0, "/dev/input/mouse#", 18); res = syz_open_dev(0x200000c0, 0x3ff, 0x400002); if (res != -1) r[3] = res; break; case 5: *(uint32_t*)0x20000140 = 2; *(uint32_t*)0x20000144 = r[3]; *(uint32_t*)0x20000148 = 1; *(uint32_t*)0x2000014c = 0; *(uint32_t*)0x20000150 = 0; *(uint32_t*)0x20000154 = 0; syscall(__NR_ioctl, r[1], 0x4018aebd, 0x20000140); break; case 6: *(uint32_t*)0x20000080 = 0; *(uint32_t*)0x20000084 = r[2]; *(uint32_t*)0x20000088 = 0; *(uint32_t*)0x2000008c = 0; *(uint32_t*)0x20000090 = 0; *(uint32_t*)0x20000094 = 0; syscall(__NR_ioctl, r[1], 0x4018aebd, 0x20000080); break; } } void execute_one() { execute(7); collide = 1; execute(7); } int main() { syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0); for (procid = 0; procid < 8; procid++) { if (fork() == 0) { for (;;) { loop(); } } } sleep(1000000); return 0; }