// https://syzkaller.appspot.com/bug?id=4c7b3b611ce34d3ef0a98634f3de098fc5c92d5b // 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 __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 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(); int fd; for (fd = 3; fd < 30; fd++) close(fd); 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 < 5 * 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 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); struct timespec ts; ts.tv_sec = 0; ts.tv_nsec = 20 * 1000 * 1000; syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts); if (__atomic_load_n(&running, __ATOMIC_RELAXED)) usleep((call == num_calls - 1) ? 10000 : 1000); break; } } } } uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}; unsigned long long procid; void execute_call(int call) { long res; switch (call) { case 0: res = syscall(__NR_pipe2, 0x20000100, 0x4000); if (res != -1) { r[0] = *(uint32_t*)0x20000100; r[1] = *(uint32_t*)0x20000104; } break; case 1: *(uint32_t*)0x20000040 = 0xffffffca; *(uint8_t*)0x20000044 = 0x4d; *(uint16_t*)0x20000045 = 0; syscall(__NR_write, r[1], 0x20000040, 7); break; case 2: memcpy((void*)0x20000080, "./file0", 8); syscall(__NR_mkdir, 0x20000080, 0); break; case 3: res = syscall(__NR_pipe2, 0x20000180, 0x80000); if (res != -1) r[2] = *(uint32_t*)0x20000180; break; case 4: memcpy((void*)0x20000000, "./file0", 8); memcpy((void*)0x20000900, "9p", 3); memcpy((void*)0x200002c0, "trans=fd,", 9); memcpy((void*)0x200002c9, "rfdno", 5); *(uint8_t*)0x200002ce = 0x3d; sprintf((char*)0x200002cf, "0x%016llx", (long long)r[0]); *(uint8_t*)0x200002e1 = 0x2c; memcpy((void*)0x200002e2, "wfdno", 5); *(uint8_t*)0x200002e7 = 0x3d; sprintf((char*)0x200002e8, "0x%016llx", (long long)r[2]); *(uint8_t*)0x200002fa = 0x2c; *(uint8_t*)0x200002fb = 0; syscall(__NR_mount, 0, 0x20000000, 0x20000900, 0x4000, 0x200002c0); break; } } void execute_one() { execute(5); } 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; }