// https://syzkaller.appspot.com/bug?id=baff5bfd0c148e6a6552e815fba942c1ac5e61b0
// 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/ioctl.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/prctl.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/fs.h>
#include <linux/futex.h>
#include <linux/types.h>

#ifndef __NR_bpf
#define __NR_bpf 321
#endif

static 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 = 0;
  for (; 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);
}

#define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off))
#define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len)               \
  *(type*)(addr) =                                                             \
      htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) |           \
            (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len))))

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, 1000000);
}

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_ACQUIRE))
      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;
}

#define SIZEOF_IO_URING_SQE 64
#define SIZEOF_IO_URING_CQE 16

#define IORING_SETUP_SQE128 (1U << 10)
#define IORING_SETUP_CQE32 (1U << 11)

struct io_sqring_offsets {
  uint32_t head;
  uint32_t tail;
  uint32_t ring_mask;
  uint32_t ring_entries;
  uint32_t flags;
  uint32_t dropped;
  uint32_t array;
  uint32_t resv1;
  uint64_t user_addr;
};

struct io_cqring_offsets {
  uint32_t head;
  uint32_t tail;
  uint32_t ring_mask;
  uint32_t ring_entries;
  uint32_t overflow;
  uint32_t cqes;
  uint32_t flags;
  uint32_t resv1;
  uint64_t user_addr;
};

struct io_uring_params {
  uint32_t sq_entries;
  uint32_t cq_entries;
  uint32_t flags;
  uint32_t sq_thread_cpu;
  uint32_t sq_thread_idle;
  uint32_t features;
  uint32_t resv[4];
  struct io_sqring_offsets sq_off;
  struct io_cqring_offsets cq_off;
};

static long io_uring_sqe_size(struct io_uring_params* params)
{
  return SIZEOF_IO_URING_SQE << !!(params->flags & IORING_SETUP_SQE128);
}

static long io_uring_cqe_size(struct io_uring_params* params)
{
  return SIZEOF_IO_URING_CQE << !!(params->flags & IORING_SETUP_CQE32);
}

#define IORING_OFF_SQ_RING 0ULL
#define IORING_OFF_SQES 0x10000000ULL
static long syz_io_uring_setup(volatile long a0, volatile long a1,
                               volatile long a2, volatile long a3,
                               volatile long a4)
{
  uint32_t entries = (uint32_t)a0;
  struct io_uring_params* setup_params = (struct io_uring_params*)a1;
  void** ring_params_ptr_out = (void**)a2;
  void** ring_ptr_out = (void**)a3;
  void** sqes_ptr_out = (void**)a4;
  uint32_t fd_io_uring = syscall(__NR_io_uring_setup, entries, setup_params);
  *ring_params_ptr_out = (void*)setup_params;
  uint32_t sq_ring_sz =
      setup_params->sq_off.array + setup_params->sq_entries * sizeof(uint32_t);
  uint32_t cq_ring_sz =
      setup_params->cq_off.cqes +
      setup_params->cq_entries * io_uring_cqe_size(setup_params);
  uint32_t ring_sz = sq_ring_sz > cq_ring_sz ? sq_ring_sz : cq_ring_sz;
  *ring_ptr_out =
      mmap(0, ring_sz, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE,
           fd_io_uring, IORING_OFF_SQ_RING);
  uint32_t sqes_sz = setup_params->sq_entries * io_uring_sqe_size(setup_params);
  *sqes_ptr_out = mmap(0, sqes_sz, PROT_READ | PROT_WRITE,
                       MAP_SHARED | MAP_POPULATE, fd_io_uring, IORING_OFF_SQES);
  uint32_t* array =
      (uint32_t*)((uintptr_t)*ring_ptr_out + setup_params->sq_off.array);
  for (uint32_t index = 0; index < setup_params->sq_entries; index++)
    array[index] = index;
  return fd_io_uring;
}

static long syz_io_uring_submit(volatile long a0, volatile long a1,
                                volatile long a2, volatile long a3)
{
  struct io_uring_params* params = (struct io_uring_params*)a0;
  char* ring_ptr = (char*)a1;
  char* sqes_ptr = (char*)a2;
  char* sqe = (char*)a3;
  uint32_t sq_ring_mask = *(uint32_t*)(ring_ptr + params->sq_off.ring_mask);
  uint32_t* sq_tail_ptr = (uint32_t*)(ring_ptr + params->sq_off.tail);
  uint32_t sq_tail = *sq_tail_ptr & sq_ring_mask;
  uint32_t sqe_size = io_uring_sqe_size(params);
  char* sqe_dest = sqes_ptr + sq_tail * sqe_size;
  memcpy(sqe_dest, sqe, sqe_size);
  uint32_t sq_tail_next = *sq_tail_ptr + 1;
  __atomic_store_n(sq_tail_ptr, sq_tail_next, __ATOMIC_RELEASE);
  return 0;
}

static long syz_ublk_setup_io_uring(volatile long a0, volatile long a1,
                                    volatile long a2, volatile long a3,
                                    volatile long a4)
{
  struct io_uring_params* params = (struct io_uring_params*)a1;
  params->flags |= IORING_SETUP_SQE128 | IORING_SETUP_CQE32;
  return syz_io_uring_setup(a0, (long)params, a2, a3, a4);
}

#define UBLK_F_USER_COPY (1UL << 7)

#define UBLK_IO_RES_OK 0
#define UBLK_IO_RES_NEED_GET_DATA 1

#define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21
#define UBLK_IO_NEED_GET_DATA 0x22

#define UBLK_U_IO_COMMIT_AND_FETCH_REQ                                         \
  _IOWR('u', UBLK_IO_COMMIT_AND_FETCH_REQ, struct ublksrv_io_cmd)
#define UBLK_U_IO_NEED_GET_DATA                                                \
  _IOWR('u', UBLK_IO_NEED_GET_DATA, struct ublksrv_io_cmd)

struct ublksrv_ctrl_cmd {
  __u32 dev_id;
  __u16 queue_id;
  __u16 len;
  __u64 addr;
  __u64 data[1];
  __u16 dev_path_len;
  __u16 pad;
  __u32 reserved;
};

struct ublksrv_ctrl_dev_info {
  __u16 nr_hw_queues;
  __u16 queue_depth;
  __u16 state;
  __u16 pad0;
  __u32 max_io_buf_bytes;
  __u32 dev_id;
  __s32 ublksrv_pid;
  __u32 pad1;
  __u64 flags;
  __u64 ublksrv_flags;
  __u32 owner_uid;
  __u32 owner_gid;
  __u64 reserved1;
  __u64 reserved2;
};

struct ublksrv_io_desc {
  __u32 op_flags;
  union {
    __u32 nr_sectors;
    __u32 nr_zones;
  };
  __u64 start_sector;
  __u64 addr;
};

struct ublksrv_io_cmd {
  __u16 q_id;
  __u16 tag;
  __s32 result;
  union {
    __u64 addr;
    __u64 zone_append_lba;
  };
};

struct io_uring_sqe {
  __u8 opcode;
  __u8 flags;
  __u16 ioprio;
  __s32 fd;
  union {
    __u64 off;
    __u64 addr2;
    struct {
      __u32 cmd_op;
      __u32 __pad1;
    };
  };
  union {
    __u64 addr;
    __u64 splice_off_in;
    struct {
      __u32 level;
      __u32 optname;
    };
  };
  __u32 len;
  union {
    __kernel_rwf_t rw_flags;
    __u32 fsync_flags;
    __u16 poll_events;
    __u32 poll32_events;
    __u32 sync_range_flags;
    __u32 msg_flags;
    __u32 timeout_flags;
    __u32 accept_flags;
    __u32 cancel_flags;
    __u32 open_flags;
    __u32 statx_flags;
    __u32 fadvise_advice;
    __u32 splice_flags;
    __u32 rename_flags;
    __u32 unlink_flags;
    __u32 hardlink_flags;
    __u32 xattr_flags;
    __u32 msg_ring_flags;
    __u32 uring_cmd_flags;
    __u32 waitid_flags;
    __u32 futex_flags;
    __u32 install_fd_flags;
    __u32 nop_flags;
    __u32 pipe_flags;
  };
  __u64 user_data;
  union {
    __u16 buf_index;
    __u16 buf_group;
  } __attribute__((packed));
  __u16 personality;
  union {
    __s32 splice_fd_in;
    __u32 file_index;
    __u32 zcrx_ifq_idx;
    __u32 optlen;
    struct {
      __u16 addr_len;
      __u16 __pad3[1];
    };
  };
  union {
    struct {
      __u64 addr3;
      __u64 __pad2[1];
    };
    struct {
      __u64 attr_ptr;
      __u64 attr_type_mask;
    };
    __u64 optval;
    __u8 cmd[0];
  };
};

static long syz_ublk_add_dev(volatile long a0, volatile long a1,
                             volatile long a2, volatile long a3,
                             volatile long a4, volatile long a5)
{
  __u32 ring_fd = (__u32)a0;
  struct io_uring_params* params = (struct io_uring_params*)a1;
  char* ring_ptr = (char*)a2;
  char* sqes_ptr = (char*)a3;
  struct io_uring_sqe* sqe = (struct io_uring_sqe*)a4;
  void** dev_info_ptr_out = (void**)a5;
  struct ublksrv_ctrl_cmd* cmd = (struct ublksrv_ctrl_cmd*)(sqe->cmd);
  struct ublksrv_ctrl_dev_info* dev_info =
      (struct ublksrv_ctrl_dev_info*)(unsigned long)(cmd->addr);
  dev_info->flags |= UBLK_F_USER_COPY;
  int ret = syz_io_uring_submit((long)params, (long)ring_ptr, (long)sqes_ptr,
                                (long)sqe);
  if (ret < 0)
    return (long)ret;
  syscall(__NR_io_uring_enter, ring_fd, 1, 1, 1, NULL, _NSIG / 8);
  *dev_info_ptr_out = (void*)dev_info;
  return dev_info->dev_id;
}

struct ublk_queue {
  __u16 q_id;
  __u32 char_dev_fd;
  struct io_uring_params params;
  __u32 ring_fd;
  char* ring_ptr;
  char* sqes_ptr;
  char* io_cmd_buf;
};

#define UBLK_MAX_QUEUE_DEPTH 4096
#define UBLK_QUEUES_OFFSET 0

#define round_up(x, y) (((x) + (y) - 1) / (y) * (y))

static long syz_ublk_setup_queues(volatile long a0, volatile long a1,
                                  volatile long a2, volatile long a3,
                                  volatile long a4, volatile long a5,
                                  volatile long a6)
{
  int char_dev_fd = (int)a0;
  struct ublksrv_ctrl_dev_info* dev_info = (struct ublksrv_ctrl_dev_info*)a1;
  struct io_uring_params* params = (struct io_uring_params*)a2;
  struct ublk_queue* queues = (struct ublk_queue*)a3;
  int queues_len = (int)a4;
  struct io_uring_sqe* sqe = (struct io_uring_sqe*)a5;
  void** queues_ptr_out = (void**)a6;
  if (char_dev_fd < 0 || !dev_info)
    return -1;
  memset(queues, 0, sizeof(struct ublk_queue) * queues_len);
  int queue_depth = dev_info->queue_depth;
  for (int q_id = 0; q_id < dev_info->nr_hw_queues; q_id++) {
    struct ublk_queue* queue = &queues[q_id];
    queue->q_id = q_id;
    queue->char_dev_fd = char_dev_fd;
    queue->params = *params;
    struct io_uring_params* temp = NULL;
    queue->ring_fd = syz_ublk_setup_io_uring(
        (long)queue_depth, (long)&queue->params, (long)&temp,
        (long)&queue->ring_ptr, (long)&queue->sqes_ptr);
    if (queue->ring_fd < 0) {
      return queue->ring_fd;
    }
    unsigned long cmd_buf_size =
        round_up(queue_depth * sizeof(struct ublksrv_io_desc), getpagesize());
    unsigned long off =
        UBLK_QUEUES_OFFSET +
        q_id * round_up(UBLK_MAX_QUEUE_DEPTH * sizeof(struct ublksrv_io_desc),
                        getpagesize());
    queue->io_cmd_buf =
        (char*)mmap(0, cmd_buf_size, PROT_READ, MAP_SHARED | MAP_POPULATE,
                    char_dev_fd, off);
    if (queue->io_cmd_buf == MAP_FAILED) {
      return -1;
    }
    for (int j = 0; j < queue_depth; j++) {
      struct ublksrv_io_cmd* cmd = (struct ublksrv_io_cmd*)(&sqe->cmd);
      cmd->q_id = q_id;
      cmd->tag = j;
      cmd->addr = 0;
      sqe->user_data = j | (sqe->cmd_op << 16);
      if (syz_io_uring_submit((long)&queue->params, (long)queue->ring_ptr,
                              (long)queue->sqes_ptr, (long)sqe) < 0) {
        return -1;
      }
      syscall(__NR_io_uring_enter, queue->ring_fd, 1, 0, 0, NULL, _NSIG / 8);
    }
  }
  *queues_ptr_out = (void*)queues;
  return 0;
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  for (int 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");
}

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)
{
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  int i, call, thread;
  for (call = 0; call < 8; 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);
      event_timedwait(&th->done, 50);
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter = 0;
  for (;; 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 (;;) {
      sleep_ms(10);
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
  }
}

uint64_t r[8] = {0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0,
                 0xffffffffffffffff, 0xffffffffffffffff};

void execute_call(int call)
{
  intptr_t res = 0;
  switch (call) {
  case 0:
    //  openat$ttynull arguments: [
    //    fd: const = 0xffffffffffffff9c (8 bytes)
    //    file: ptr[in, buffer] {
    //      buffer: {2f 64 65 76 2f 74 74 79 6e 75 6c 6c 00} (length 0xd)
    //    }
    //    flags: open_flags = 0x103902 (4 bytes)
    //    mode: const = 0x0 (2 bytes)
    //  ]
    //  returns fd_tty
    memcpy((void*)0x200000000000, "/dev/ttynull\000", 13);
    res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul,
                  /*file=*/0x200000000000ul,
                  /*flags=O_SYNC|O_NONBLOCK|O_NOCTTY|FASYNC|O_RDWR*/ 0x103902,
                  /*mode=*/0);
    if (res != -1)
      r[0] = res;
    break;
  case 1:
    //  dup arguments: [
    //    oldfd: fd (resource)
    //  ]
    //  returns fd
    syscall(__NR_dup, /*oldfd=*/r[0]);
    break;
  case 2:
    //  syz_ublk_setup_io_uring arguments: [
    //    entries: int32 = 0x1d (4 bytes)
    //    params: ptr[inout, io_uring_params] {
    //      io_uring_params {
    //        sq_entries: int32 = 0x0 (4 bytes)
    //        cq_entries: int32 = 0x30b5 (4 bytes)
    //        flags: io_uring_setup_flags = 0x0 (4 bytes)
    //        sq_thread_cpu: int32 = 0x2 (4 bytes)
    //        sq_thread_idle: int32 = 0x95 (4 bytes)
    //        features: int32 = 0x0 (4 bytes)
    //        wq_fd: fd_io_uring (resource)
    //        resv: buffer: {00 00 00 00 00 00 00 00 00 00 00 00} (length 0xc)
    //        sq_off: io_sqring_offsets {
    //          head: int32 = 0x0 (4 bytes)
    //          tail: int32 = 0x0 (4 bytes)
    //          ring_mask: int32 = 0x0 (4 bytes)
    //          ring_entries: int32 = 0x0 (4 bytes)
    //          flags: int32 = 0x0 (4 bytes)
    //          dropped: int32 = 0x0 (4 bytes)
    //          array: int32 = 0x0 (4 bytes)
    //          resv1: int32 = 0x0 (4 bytes)
    //          user_addr: int64 = 0x0 (8 bytes)
    //        }
    //        cq_off: io_cqring_offsets {
    //          head: int32 = 0x0 (4 bytes)
    //          tail: int32 = 0x0 (4 bytes)
    //          ring_mask: int32 = 0x0 (4 bytes)
    //          ring_entries: int32 = 0x0 (4 bytes)
    //          overflow: int32 = 0x0 (4 bytes)
    //          cqes: int32 = 0x0 (4 bytes)
    //          flags: int32 = 0x0 (4 bytes)
    //          resv1: int32 = 0x0 (4 bytes)
    //          user_addr: int64 = 0x0 (8 bytes)
    //        }
    //      }
    //    }
    //    ring_params_ptr: ptr[out, ring_params_ptr] {
    //      ring_params_ptr (resource)
    //    }
    //    ring_ptr: ptr[out, ring_ptr] {
    //      ring_ptr (resource)
    //    }
    //    sqes_ptr: ptr[out, sqes_ptr] {
    //      sqes_ptr (resource)
    //    }
    //  ]
    //  returns fd_io_uring
    *(uint32_t*)0x200000000044 = 0x30b5;
    *(uint32_t*)0x200000000048 = 0;
    *(uint32_t*)0x20000000004c = 2;
    *(uint32_t*)0x200000000050 = 0x95;
    *(uint32_t*)0x200000000058 = -1;
    memset((void*)0x20000000005c, 0, 12);
    res = -1;
    res = syz_ublk_setup_io_uring(/*entries=*/0x1d, /*params=*/0x200000000040,
                                  /*ring_params_ptr=*/0x200000000100,
                                  /*ring_ptr=*/0x200000000280,
                                  /*sqes_ptr=*/0x200000000140);
    if (res != -1) {
      r[1] = res;
      r[2] = *(uint64_t*)0x200000000100;
      r[3] = *(uint64_t*)0x200000000280;
      r[4] = *(uint64_t*)0x200000000140;
    }
    break;
  case 3:
    //  syz_ublk_add_dev arguments: [
    //    fd_io_uring: fd_io_uring (resource)
    //    ring_params_ptr: ring_params_ptr (resource)
    //    ring_ptr: ring_ptr (resource)
    //    sqes_ptr: sqes_ptr (resource)
    //    sqe: ptr[inout, io_uring_sqe_uring[fd_ublk_ctrl,
    //    const[UBLK_U_CMD_ADD_DEV, int32], ublk_ctrl_cmd$add_dev, int64]] {
    //      io_uring_sqe_uring[fd_ublk_ctrl, const[UBLK_U_CMD_ADD_DEV, int32],
    //      ublk_ctrl_cmd$add_dev, int64] {
    //        opcode: const = 0x2e (1 bytes)
    //        flags: iosqe_flags = 0x14 (1 bytes)
    //        ioprio: const = 0x0 (2 bytes)
    //        fd: fd_ublk_ctrl (resource)
    //        cmd_op: const = 0xc0207504 (4 bytes)
    //        pad1: const = 0x0 (4 bytes)
    //        addr: const = 0x0 (8 bytes)
    //        len: const = 0x0 (4 bytes)
    //        uring_flags: uring_cmd_flags = 0x0 (4 bytes)
    //        user_data: int64 = 0x4 (8 bytes)
    //        buf_index_unused: const = 0x0 (2 bytes)
    //        ioring_personality_id: ioring_personality_id (resource)
    //        pad_unused: buffer: {00 00 00 00} (length 0x4)
    //        cmd: ublk_ctrl_cmd[const[-1, int32], len[addr, int16], ptr64[in,
    //        ublk_ctrl_dev_info_new], const[0, int64]] {
    //          dev_id: const = 0xffffffff (4 bytes)
    //          queue_id: const = 0xffff (2 bytes)
    //          len: len = 0x40 (2 bytes)
    //          addr: ptr[in, ublk_ctrl_dev_info_new] {
    //            union ublk_ctrl_dev_info_new {
    //              any_dev: ublk_ctrl_dev_info[int32] {
    //                nr_hw_queues: int16 = 0x3 (2 bytes)
    //                queue_depth: int16 = 0xe26 (2 bytes)
    //                state: const = 0x0 (2 bytes)
    //                pad0: const = 0x0 (2 bytes)
    //                max_io_buf_bytes: const = 0x1000 (4 bytes)
    //                dev_id: int32 = 0x10010001 (4 bytes)
    //                ublk_pid: pid (resource)
    //                pad1: const = 0x0 (4 bytes)
    //                flags: ublk_f_flags = 0xcd (8 bytes)
    //                ublk_flags: const = 0x0 (8 bytes)
    //                owner_uid: const = 0x0 (4 bytes)
    //                owner_gid: const = 0x0 (4 bytes)
    //                reserved1: const = 0x0 (8 bytes)
    //                reserved2: const = 0x0 (8 bytes)
    //              }
    //            }
    //          }
    //          data: const = 0x0 (8 bytes)
    //          dev_path_len: const = 0x0 (2 bytes)
    //          pad: const = 0x0 (2 bytes)
    //          reserved: const = 0x0 (4 bytes)
    //          pad2_unused: buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00 00
    //          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    //          00 00 00 00 00 00 00 00 00 00 00 00 00} (length 0x30)
    //        }
    //      }
    //    }
    //    dev_info_ptr: ptr[out, dev_info_ptr] {
    //      dev_info_ptr (resource)
    //    }
    //  ]
    //  returns ublk_dev_id
    *(uint8_t*)0x2000000003c0 = 0x2e;
    *(uint8_t*)0x2000000003c1 = 0x14;
    *(uint16_t*)0x2000000003c2 = 0;
    *(uint32_t*)0x2000000003c4 = -1;
    *(uint32_t*)0x2000000003c8 = 0xc0207504;
    *(uint32_t*)0x2000000003cc = 0;
    *(uint64_t*)0x2000000003d0 = 0;
    *(uint32_t*)0x2000000003d8 = 0;
    *(uint32_t*)0x2000000003dc = 0;
    *(uint64_t*)0x2000000003e0 = 4;
    *(uint16_t*)0x2000000003e8 = 0;
    *(uint16_t*)0x2000000003ea = 0;
    memset((void*)0x2000000003ec, 0, 4);
    *(uint32_t*)0x2000000003f0 = -1;
    *(uint16_t*)0x2000000003f4 = -1;
    *(uint16_t*)0x2000000003f6 = 0x40;
    *(uint64_t*)0x2000000003f8 = 0x2000000004c0;
    *(uint16_t*)0x2000000004c0 = 3;
    *(uint16_t*)0x2000000004c2 = 0xe26;
    *(uint16_t*)0x2000000004c4 = 0;
    *(uint16_t*)0x2000000004c6 = 0;
    *(uint32_t*)0x2000000004c8 = 0x1000;
    *(uint32_t*)0x2000000004cc = 0x10010001;
    *(uint32_t*)0x2000000004d0 = -1;
    *(uint32_t*)0x2000000004d4 = 0;
    *(uint64_t*)0x2000000004d8 = 0xcd;
    *(uint64_t*)0x2000000004e0 = 0;
    *(uint32_t*)0x2000000004e8 = 0;
    *(uint32_t*)0x2000000004ec = 0;
    *(uint64_t*)0x2000000004f0 = 0;
    *(uint64_t*)0x2000000004f8 = 0;
    *(uint64_t*)0x200000000400 = 0;
    *(uint16_t*)0x200000000408 = 0;
    *(uint16_t*)0x20000000040a = 0;
    *(uint32_t*)0x20000000040c = 0;
    memset((void*)0x200000000410, 0, 48);
    res = -1;
    res = syz_ublk_add_dev(/*fd_io_uring=*/r[1], /*ring_params_ptr=*/r[2],
                           /*ring_ptr=*/r[3], /*sqes_ptr=*/r[4],
                           /*sqe=*/0x2000000003c0,
                           /*dev_info_ptr=*/0x200000000480);
    if (res != -1)
      r[5] = *(uint64_t*)0x200000000480;
    break;
  case 4:
    //  socket$inet6_tcp arguments: [
    //    domain: const = 0xa (8 bytes)
    //    type: const = 0x1 (8 bytes)
    //    proto: const = 0x0 (4 bytes)
    //  ]
    //  returns sock_tcp6
    res = syscall(__NR_socket, /*domain=*/0xaul, /*type=*/1ul, /*proto=*/0);
    if (res != -1)
      r[6] = res;
    break;
  case 5:
    //  dup arguments: [
    //    oldfd: fd (resource)
    //  ]
    //  returns fd
    res = syscall(__NR_dup, /*oldfd=*/r[6]);
    if (res != -1)
      r[7] = res;
    break;
  case 6:
    //  syz_ublk_setup_queues arguments: [
    //    fd_ublk_ch: fd_ublk_ch (resource)
    //    dev_info_ptr: dev_info_ptr (resource)
    //    params: ptr[in, io_uring_params] {
    //      io_uring_params {
    //        sq_entries: int32 = 0x0 (4 bytes)
    //        cq_entries: int32 = 0x1 (4 bytes)
    //        flags: io_uring_setup_flags = 0x0 (4 bytes)
    //        sq_thread_cpu: int32 = 0x3 (4 bytes)
    //        sq_thread_idle: int32 = 0x257 (4 bytes)
    //        features: int32 = 0x0 (4 bytes)
    //        wq_fd: fd_io_uring (resource)
    //        resv: buffer: {00 00 00 00 00 00 00 00 00 00 00 00} (length 0xc)
    //        sq_off: io_sqring_offsets {
    //          head: int32 = 0x0 (4 bytes)
    //          tail: int32 = 0x0 (4 bytes)
    //          ring_mask: int32 = 0x0 (4 bytes)
    //          ring_entries: int32 = 0x0 (4 bytes)
    //          flags: int32 = 0x0 (4 bytes)
    //          dropped: int32 = 0x0 (4 bytes)
    //          array: int32 = 0x0 (4 bytes)
    //          resv1: int32 = 0x0 (4 bytes)
    //          user_addr: int64 = 0x0 (8 bytes)
    //        }
    //        cq_off: io_cqring_offsets {
    //          head: int32 = 0x0 (4 bytes)
    //          tail: int32 = 0x0 (4 bytes)
    //          ring_mask: int32 = 0x0 (4 bytes)
    //          ring_entries: int32 = 0x0 (4 bytes)
    //          overflow: int32 = 0x0 (4 bytes)
    //          cqes: int32 = 0x0 (4 bytes)
    //          flags: int32 = 0x0 (4 bytes)
    //          resv1: int32 = 0x0 (4 bytes)
    //          user_addr: int64 = 0x0 (8 bytes)
    //        }
    //      }
    //    }
    //    queues: ptr[out, array[ublk_queue]] {
    //      array[ublk_queue] {
    //        ublk_queue {
    //          queue_id: int16 = 0x0 (2 bytes)
    //          pad1: const = 0x0 (2 bytes)
    //          fd_ublk_ch: fd_ublk_ch (resource)
    //          params: io_uring_params {
    //            sq_entries: int32 = 0x0 (4 bytes)
    //            cq_entries: int32 = 0x7ffffe (4 bytes)
    //            flags: io_uring_setup_flags = 0x8 (4 bytes)
    //            sq_thread_cpu: int32 = 0x2000 (4 bytes)
    //            sq_thread_idle: int32 = 0x10000004 (4 bytes)
    //            features: int32 = 0x0 (4 bytes)
    //            wq_fd: fd_io_uring (resource)
    //            resv: buffer: (DirOut)
    //            sq_off: io_sqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              dropped: int32 = 0x0 (4 bytes)
    //              array: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //            cq_off: io_cqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              overflow: int32 = 0x0 (4 bytes)
    //              cqes: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //          }
    //          ring_fd: fd_io_uring (resource)
    //          pad2: const = 0x0 (4 bytes)
    //          ring_ptr: ring_ptr (resource)
    //          sqes_ptr: sqes_ptr (resource)
    //          io_cmd_buf: intptr = 0x0 (8 bytes)
    //        }
    //        ublk_queue {
    //          queue_id: int16 = 0x0 (2 bytes)
    //          pad1: const = 0x0 (2 bytes)
    //          fd_ublk_ch: fd_ublk_ch (resource)
    //          params: io_uring_params {
    //            sq_entries: int32 = 0x0 (4 bytes)
    //            cq_entries: int32 = 0x35bc (4 bytes)
    //            flags: io_uring_setup_flags = 0x1 (4 bytes)
    //            sq_thread_cpu: int32 = 0xfffffffd (4 bytes)
    //            sq_thread_idle: int32 = 0x30b (4 bytes)
    //            features: int32 = 0x0 (4 bytes)
    //            wq_fd: fd_io_uring (resource)
    //            resv: buffer: (DirOut)
    //            sq_off: io_sqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              dropped: int32 = 0x0 (4 bytes)
    //              array: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //            cq_off: io_cqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              overflow: int32 = 0x0 (4 bytes)
    //              cqes: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //          }
    //          ring_fd: fd_io_uring (resource)
    //          pad2: const = 0x0 (4 bytes)
    //          ring_ptr: ring_ptr (resource)
    //          sqes_ptr: sqes_ptr (resource)
    //          io_cmd_buf: intptr = 0x0 (8 bytes)
    //        }
    //        ublk_queue {
    //          queue_id: int16 = 0x0 (2 bytes)
    //          pad1: const = 0x0 (2 bytes)
    //          fd_ublk_ch: fd_ublk_ch (resource)
    //          params: io_uring_params {
    //            sq_entries: int32 = 0x0 (4 bytes)
    //            cq_entries: int32 = 0xc1cf (4 bytes)
    //            flags: io_uring_setup_flags = 0x0 (4 bytes)
    //            sq_thread_cpu: int32 = 0x0 (4 bytes)
    //            sq_thread_idle: int32 = 0x1f0 (4 bytes)
    //            features: int32 = 0x0 (4 bytes)
    //            wq_fd: fd_io_uring (resource)
    //            resv: buffer: (DirOut)
    //            sq_off: io_sqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              dropped: int32 = 0x0 (4 bytes)
    //              array: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //            cq_off: io_cqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              overflow: int32 = 0x0 (4 bytes)
    //              cqes: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //          }
    //          ring_fd: fd_io_uring (resource)
    //          pad2: const = 0x0 (4 bytes)
    //          ring_ptr: ring_ptr (resource)
    //          sqes_ptr: sqes_ptr (resource)
    //          io_cmd_buf: intptr = 0x0 (8 bytes)
    //        }
    //        ublk_queue {
    //          queue_id: int16 = 0x0 (2 bytes)
    //          pad1: const = 0x0 (2 bytes)
    //          fd_ublk_ch: fd_ublk_ch (resource)
    //          params: io_uring_params {
    //            sq_entries: int32 = 0x0 (4 bytes)
    //            cq_entries: int32 = 0x0 (4 bytes)
    //            flags: io_uring_setup_flags = 0x8200 (4 bytes)
    //            sq_thread_cpu: int32 = 0x2 (4 bytes)
    //            sq_thread_idle: int32 = 0x367 (4 bytes)
    //            features: int32 = 0x0 (4 bytes)
    //            wq_fd: fd_io_uring (resource)
    //            resv: buffer: (DirOut)
    //            sq_off: io_sqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              dropped: int32 = 0x0 (4 bytes)
    //              array: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //            cq_off: io_cqring_offsets {
    //              head: int32 = 0x0 (4 bytes)
    //              tail: int32 = 0x0 (4 bytes)
    //              ring_mask: int32 = 0x0 (4 bytes)
    //              ring_entries: int32 = 0x0 (4 bytes)
    //              overflow: int32 = 0x0 (4 bytes)
    //              cqes: int32 = 0x0 (4 bytes)
    //              flags: int32 = 0x0 (4 bytes)
    //              resv1: int32 = 0x0 (4 bytes)
    //              user_addr: int64 = 0x0 (8 bytes)
    //            }
    //          }
    //          ring_fd: fd_io_uring (resource)
    //          pad2: const = 0x0 (4 bytes)
    //          ring_ptr: ring_ptr (resource)
    //          sqes_ptr: sqes_ptr (resource)
    //          io_cmd_buf: intptr = 0x0 (8 bytes)
    //        }
    //      }
    //    }
    //    nr_queues: const = 0x1 (8 bytes)
    //    sqe: ptr[inout, io_uring_sqe_uring[fd_ublk_ch,
    //    const[UBLK_U_IO_FETCH_REQ, int32], ublk_io_cmd$fetch_req,
    //    user_data[UBLK_U_IO_FETCH_REQ]]] {
    //      io_uring_sqe_uring[fd_ublk_ch, const[UBLK_U_IO_FETCH_REQ, int32],
    //      ublk_io_cmd$fetch_req, user_data[UBLK_U_IO_FETCH_REQ]] {
    //        opcode: const = 0x2e (1 bytes)
    //        flags: iosqe_flags = 0x44 (1 bytes)
    //        ioprio: const = 0x0 (2 bytes)
    //        fd: fd_ublk_ch (resource)
    //        cmd_op: const = 0xc0107520 (4 bytes)
    //        pad1: const = 0x0 (4 bytes)
    //        addr: const = 0x0 (8 bytes)
    //        len: const = 0x0 (4 bytes)
    //        uring_flags: uring_cmd_flags = 0x0 (4 bytes)
    //        user_data: user_data[UBLK_U_IO_FETCH_REQ] {
    //          tag: int64 = 0x0 (0 bytes)
    //          cmd: const = 0xc0107520 (0 bytes)
    //          pad: const = 0x0 (8 bytes)
    //        }
    //        buf_index_unused: const = 0x1f (2 bytes)
    //        ioring_personality_id: ioring_personality_id (resource)
    //        pad_unused: buffer: {00 00 00 00} (length 0x4)
    //        cmd: ublk_io_cmd[int16[0:UBLK_MAX_HW_QUEUES],
    //        int16[0:UBLK_MAX_QUEUE_DEPTH], const[0, int32], ptr64[inout,
    //        ublk_io_buf_u]] {
    //          q_id: int16 = 0xfff9 (2 bytes)
    //          tag: int16 = 0x4 (2 bytes)
    //          result: const = 0x0 (4 bytes)
    //          addr: nil
    //          pad: buffer: {00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    //          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    //          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
    //          00 00 00 00 00} (length 0x40)
    //        }
    //      }
    //    }
    //    ublk_queues_ptr: nil
    //  ]
    *(uint32_t*)0x200000000184 = 1;
    *(uint32_t*)0x200000000188 = 0;
    *(uint32_t*)0x20000000018c = 3;
    *(uint32_t*)0x200000000190 = 0x257;
    *(uint32_t*)0x200000000198 = -1;
    memset((void*)0x20000000019c, 0, 12);
    *(uint32_t*)0x20000000080c = 0x7ffffe;
    *(uint32_t*)0x200000000810 = 8;
    *(uint32_t*)0x200000000814 = 0x2000;
    *(uint32_t*)0x200000000818 = 0x10000004;
    *(uint32_t*)0x200000000820 = -1;
    *(uint32_t*)0x2000000008ac = 0x35bc;
    *(uint32_t*)0x2000000008b0 = 1;
    *(uint32_t*)0x2000000008b4 = 0xfffffffd;
    *(uint32_t*)0x2000000008b8 = 0x30b;
    *(uint32_t*)0x2000000008c0 = -1;
    *(uint32_t*)0x20000000094c = 0xc1cf;
    *(uint32_t*)0x200000000950 = 0;
    *(uint32_t*)0x200000000954 = 0;
    *(uint32_t*)0x200000000958 = 0x1f0;
    *(uint32_t*)0x200000000960 = r[7];
    *(uint32_t*)0x2000000009ec = 0;
    *(uint32_t*)0x2000000009f0 = 0x8200;
    *(uint32_t*)0x2000000009f4 = 2;
    *(uint32_t*)0x2000000009f8 = 0x367;
    *(uint32_t*)0x200000000a00 = -1;
    *(uint8_t*)0x200000000340 = 0x2e;
    *(uint8_t*)0x200000000341 = 0x44;
    *(uint16_t*)0x200000000342 = 0;
    *(uint32_t*)0x200000000344 = -1;
    *(uint32_t*)0x200000000348 = 0xc0107520;
    *(uint32_t*)0x20000000034c = 0;
    *(uint64_t*)0x200000000350 = 0;
    *(uint32_t*)0x200000000358 = 0;
    *(uint32_t*)0x20000000035c = 0;
    STORE_BY_BITMASK(uint64_t, , 0x200000000360, 0, 0, 16);
    STORE_BY_BITMASK(uint64_t, , 0x200000000360, 0xc0107520, 16, 32);
    STORE_BY_BITMASK(uint64_t, , 0x200000000360, 0, 48, 16);
    *(uint16_t*)0x200000000368 = 0x1f;
    *(uint16_t*)0x20000000036a = 0;
    memset((void*)0x20000000036c, 0, 4);
    *(uint16_t*)0x200000000370 = 0xfff9;
    *(uint16_t*)0x200000000372 = 4;
    *(uint32_t*)0x200000000374 = 0;
    *(uint64_t*)0x200000000378 = 0;
    memset((void*)0x200000000380, 0, 64);
    syz_ublk_setup_queues(/*fd_ublk_ch=*/r[7], /*dev_info_ptr=*/r[5],
                          /*params=*/0x200000000180, /*queues=*/0x200000000800,
                          /*nr_queues=*/1, /*sqe=*/0x200000000340,
                          /*ublk_queues_ptr=*/0);
    break;
  case 7:
    //  bpf$MAP_CREATE_CONST_STR arguments: [
    //    cmd: const = 0x0 (8 bytes)
    //    arg: ptr[inout, array[ANYUNION]] {
    //      array[ANYUNION] {
    //        union ANYUNION {
    //          ANYBLOB: buffer: {02 00 00 00 04} (length 0x5)
    //        }
    //        union ANYUNION {
    //          ANYRES32: ANYRES32 (resource)
    //        }
    //      }
    //    }
    //    size: len = 0x48 (8 bytes)
    //  ]
    //  returns fd_bpf_const_str_map
    memcpy((void*)0x200000000340, "\x02\x00\x00\x00\x04", 5);
    *(uint32_t*)0x200000000345 = 0;
    syscall(__NR_bpf, /*cmd=*/0ul, /*arg=*/0x200000000340ul, /*size=*/0x48ul);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  for (procid = 0; procid < 5; procid++) {
    if (fork() == 0) {
      loop();
    }
  }
  sleep(1000000);
  return 0;
}