text: // memory leak in vq_meta_prefetch
  // https://syzkaller.appspot.com/bug?id=dfa19d32c9d63f0f3faf26223e447c5435894d50
  // status:open
  // autogenerated by syzkaller (https://github.com/google/syzkaller)
  
  #define _GNU_SOURCE
  
  #include <dirent.h>
  #include <endian.h>
  #include <errno.h>
  #include <fcntl.h>
  #include <pthread.h>
  #include <signal.h>
  #include <stdarg.h>
  #include <stdbool.h>
  #include <stdint.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <sys/prctl.h>
  #include <sys/socket.h>
  #include <sys/stat.h>
  #include <sys/syscall.h>
  #include <sys/types.h>
  #include <sys/wait.h>
  #include <time.h>
  #include <unistd.h>
  
  #include <linux/futex.h>
  #include <linux/genetlink.h>
  #include <linux/netlink.h>
  
  unsigned long long procid;
  
  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);
  }
  
  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_RELAXED))
        return 1;
      now = current_time_ms();
      if (now - start > timeout)
        return 0;
    }
  }
  
  static bool write_file(const char* file, const char* what, ...)
  {
    char buf[1024];
    va_list args;
    va_start(args, what);
    vsnprintf(buf, sizeof(buf), what, args);
    va_end(args);
    buf[sizeof(buf) - 1] = 0;
    int len = strlen(buf);
    int fd = open(file, O_WRONLY | O_CLOEXEC);
    if (fd == -1)
      return false;
    if (write(fd, buf, len) != len) {
      int err = errno;
      close(fd);
      errno = err;
      return false;
    }
    close(fd);
    return true;
  }
  
  static long syz_genetlink_get_family_id(volatile long name)
  {
    char buf[512] = {0};
    struct nlmsghdr* hdr = (struct nlmsghdr*)buf;
    struct genlmsghdr* genlhdr = (struct genlmsghdr*)NLMSG_DATA(hdr);
    struct nlattr* attr = (struct nlattr*)(genlhdr + 1);
    hdr->nlmsg_len =
        sizeof(*hdr) + sizeof(*genlhdr) + sizeof(*attr) + GENL_NAMSIZ;
    hdr->nlmsg_type = GENL_ID_CTRL;
    hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
    genlhdr->cmd = CTRL_CMD_GETFAMILY;
    attr->nla_type = CTRL_ATTR_FAMILY_NAME;
    attr->nla_len = sizeof(*attr) + GENL_NAMSIZ;
    strncpy((char*)(attr + 1), (char*)name, GENL_NAMSIZ);
    struct iovec iov = {hdr, hdr->nlmsg_len};
    struct sockaddr_nl addr = {0};
    addr.nl_family = AF_NETLINK;
    int fd = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
    if (fd == -1) {
      return -1;
    }
    struct msghdr msg = {&addr, sizeof(addr), &iov, 1, NULL, 0, 0};
    if (sendmsg(fd, &msg, 0) == -1) {
      close(fd);
      return -1;
    }
    ssize_t n = recv(fd, buf, sizeof(buf), 0);
    close(fd);
    if (n <= 0) {
      return -1;
    }
    if (hdr->nlmsg_type != GENL_ID_CTRL) {
      return -1;
    }
    for (; (char*)attr < buf + n;
         attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
      if (attr->nla_type == CTRL_ATTR_FAMILY_ID)
        return *(uint16_t*)(attr + 1);
    }
    return -1;
  }
  
  static void kill_and_wait(int pid, int* status)
  {
    kill(-pid, SIGKILL);
    kill(pid, SIGKILL);
    int i;
    for (i = 0; i < 100; i++) {
      if (waitpid(-1, status, WNOHANG | __WALL) == pid)
        return;
      usleep(1000);
    }
    DIR* dir = opendir("/sys/fs/fuse/connections");
    if (dir) {
      for (;;) {
        struct dirent* ent = readdir(dir);
        if (!ent)
          break;
        if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
          continue;
        char abort[300];
        snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
                 ent->d_name);
        int fd = open(abort, O_WRONLY);
        if (fd == -1) {
          continue;
        }
        if (write(fd, abort, 1) < 0) {
        }
        close(fd);
      }
      closedir(dir);
    } else {
    }
    while (waitpid(-1, status, __WALL) != pid) {
    }
  }
  
  static void setup_test()
  {
    prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
    setpgrp();
    write_file("/proc/self/oom_score_adj", "1000");
  }
  
  #define KMEMLEAK_FILE "/sys/kernel/debug/kmemleak"
  
  static void setup_leak()
  {
    if (!write_file(KMEMLEAK_FILE, "scan"))
      exit(1);
    sleep(5);
    if (!write_file(KMEMLEAK_FILE, "scan"))
      exit(1);
    if (!write_file(KMEMLEAK_FILE, "clear"))
      exit(1);
  }
  
  static void check_leaks(void)
  {
    int fd = open(KMEMLEAK_FILE, O_RDWR);
    if (fd == -1)
      exit(1);
    uint64_t start = current_time_ms();
    if (write(fd, "scan", 4) != 4)
      exit(1);
    sleep(1);
    while (current_time_ms() - start < 4 * 1000)
      sleep(1);
    if (write(fd, "scan", 4) != 4)
      exit(1);
    static char buf[128 << 10];
    ssize_t n = read(fd, buf, sizeof(buf) - 1);
    if (n < 0)
      exit(1);
    int nleaks = 0;
    if (n != 0) {
      sleep(1);
      if (write(fd, "scan", 4) != 4)
        exit(1);
      if (lseek(fd, 0, SEEK_SET) < 0)
        exit(1);
      n = read(fd, buf, sizeof(buf) - 1);
      if (n < 0)
        exit(1);
      buf[n] = 0;
      char* pos = buf;
      char* end = buf + n;
      while (pos < end) {
        char* next = strstr(pos + 1, "unreferenced object");
        if (!next)
          next = end;
        char prev = *next;
        *next = 0;
        fprintf(stderr, "BUG: memory leak\n%s\n", pos);
        *next = prev;
        pos = next;
        nleaks++;
      }
    }
    if (write(fd, "clear", 5) != 5)
      exit(1);
    close(fd);
    if (nleaks)
      exit(1);
  }
  
  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 execute_one(void)
  {
    int i, call, thread;
    int collide = 0;
  again:
    for (call = 0; call < 9; 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;
    }
  }
  
  static void execute_one(void);
  
  #define WAIT_FLAGS __WALL
  
  static void loop(void)
  {
    int iter;
    for (iter = 0;; iter++) {
      int pid = fork();
      if (pid < 0)
        exit(1);
      if (pid == 0) {
        setup_test();
        execute_one();
        exit(0);
      }
      int status = 0;
      uint64_t start = current_time_ms();
      for (;;) {
        if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
          break;
        sleep_ms(1);
        if (current_time_ms() - start < 5 * 1000)
          continue;
        kill_and_wait(pid, &status);
        break;
      }
      check_leaks();
    }
  }
  
  uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff};
  
  void execute_call(int call)
  {
    intptr_t res;
    switch (call) {
    case 0:
      memcpy((void*)0x20000040, "/dev/vhost-net\000", 15);
      res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000040, 2, 0);
      if (res != -1)
        r[0] = res;
      break;
    case 1:
      syscall(__NR_ioctl, r[0], 0x40000000af01, 0);
      break;
    case 2:
      memcpy((void*)0x20000000, "/dev/audio\000", 11);
      res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000000, 0, 0);
      if (res != -1)
        r[1] = res;
      break;
    case 3:
      syscall(__NR_close, r[1]);
      break;
    case 4:
      syscall(__NR_socket, 0x11, 3, 0x300);
      break;
    case 5:
      *(uint32_t*)0x20b04000 = 0;
      *(uint32_t*)0x20b04004 = 0;
      *(uint64_t*)0x20b04008 = 0;
      *(uint64_t*)0x20b04010 = 0x20034000;
      *(uint64_t*)0x20b04018 = 0;
      *(uint64_t*)0x20b04020 = 0;
      syscall(__NR_ioctl, r[0], 0x4028af11, 0x20b04000);
      break;
    case 6:
      syscall(__NR_ioctl, r[0], 0x4008af03, 0x20001400);
      break;
    case 7:
      *(uint32_t*)0x20d7c000 = 0;
      *(uint32_t*)0x20d7c004 = r[1];
      syscall(__NR_ioctl, r[0], 0x4008af30, 0x20d7c000);
      break;
    case 8:
      memcpy((void*)0x200000c0, "TIPCv2\000", 7);
      syz_genetlink_get_family_id(0x200000c0);
      break;
    }
  }
  int main(void)
  {
    syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
    setup_leak();
    for (procid = 0; procid < 8; procid++) {
      if (fork() == 0) {
        loop();
      }
    }
    sleep(1000000);
    return 0;
  }
  