// https://syzkaller.appspot.com/bug?id=8f3b2563e9397b1b72627450a5347f04b48630b9
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

#include <linux/loop.h>

#ifndef __NR_memfd_create
#define __NR_memfd_create 319
#endif

static unsigned long long procid;

struct fs_image_segment {
  void* data;
  uintptr_t size;
  uintptr_t offset;
};
static int setup_loop_device(long unsigned size, long unsigned nsegs,
                             struct fs_image_segment* segs,
                             const char* loopname, int* memfd_p, int* loopfd_p)
{
  int err = 0, loopfd = -1;
  int memfd = syscall(__NR_memfd_create, "syzkaller", 0);
  if (memfd == -1) {
    err = errno;
    goto error;
  }
  if (ftruncate(memfd, size)) {
    err = errno;
    goto error_close_memfd;
  }
  for (size_t i = 0; i < nsegs; i++) {
    if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) {
    }
  }
  loopfd = open(loopname, O_RDWR);
  if (loopfd == -1) {
    err = errno;
    goto error_close_memfd;
  }
  if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
    if (errno != EBUSY) {
      err = errno;
      goto error_close_loop;
    }
    ioctl(loopfd, LOOP_CLR_FD, 0);
    usleep(1000);
    if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
      err = errno;
      goto error_close_loop;
    }
  }
  *memfd_p = memfd;
  *loopfd_p = loopfd;
  return 0;

error_close_loop:
  close(loopfd);
error_close_memfd:
  close(memfd);
error:
  errno = err;
  return -1;
}

static long syz_mount_image(volatile long fsarg, volatile long dir,
                            volatile unsigned long size,
                            volatile unsigned long nsegs,
                            volatile long segments, volatile long flags,
                            volatile long optsarg, volatile long change_dir)
{
  struct fs_image_segment* segs = (struct fs_image_segment*)segments;
  int res = -1, err = 0, loopfd = -1, memfd = -1, need_loop_device = !!segs;
  char* mount_opts = (char*)optsarg;
  char* target = (char*)dir;
  char* fs = (char*)fsarg;
  char* source = NULL;
  char loopname[64];
  if (need_loop_device) {
    memset(loopname, 0, sizeof(loopname));
    snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid);
    if (setup_loop_device(size, nsegs, segs, loopname, &memfd, &loopfd) == -1)
      return -1;
    source = loopname;
  }
  mkdir(target, 0777);
  char opts[256];
  memset(opts, 0, sizeof(opts));
  if (strlen(mount_opts) > (sizeof(opts) - 32)) {
  }
  strncpy(opts, mount_opts, sizeof(opts) - 32);
  if (strcmp(fs, "iso9660") == 0) {
    flags |= MS_RDONLY;
  } else if (strncmp(fs, "ext", 3) == 0) {
    if (strstr(opts, "errors=panic") || strstr(opts, "errors=remount-ro") == 0)
      strcat(opts, ",errors=continue");
  } else if (strcmp(fs, "xfs") == 0) {
    strcat(opts, ",nouuid");
  }
  res = mount(source, target, fs, flags, opts);
  if (res == -1) {
    err = errno;
    goto error_clear_loop;
  }
  res = open(target, O_RDONLY | O_DIRECTORY);
  if (res == -1) {
    err = errno;
    goto error_clear_loop;
  }
  if (change_dir) {
    res = chdir(target);
    if (res == -1) {
      err = errno;
    }
  }

error_clear_loop:
  if (need_loop_device) {
    ioctl(loopfd, LOOP_CLR_FD, 0);
    close(loopfd);
    close(memfd);
  }
  errno = err;
  return res;
}

int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);

  memcpy((void*)0x200000c0, "v7\000", 3);
  memcpy((void*)0x20000000, "./file0\000", 8);
  *(uint64_t*)0x20000080 = 0x20000140;
  memcpy((void*)0x20000140,
         "\x2d\x78\xec\x1e\x86\x53\x46\xd5\xfe\x07\x0d\xe5\x6e\x61\x23\xa0\xe5"
         "\x40\x68\x6c\x1f\x1e\x43\xe2\x14\x3e\x43\x4c\xcf\xe2\xe5\x04\xc2\x99"
         "\x02\x1a\x04\xb1\x9b\x51\x5c\x53\x09\x12\x64\x0c\x97\x87\x1b\xe1\xe1"
         "\x3a\xa5\x96\x5e\xe2\x1c\x6e\x9d\x06\xce\x06\xd7\xc2\xe5\x97\x40\x6b"
         "\x11\x2b\x6f\x0a\xbe\x00\x40\x00\x00\x03\xfb\x93\x79\xa0\x08\xb9\xe7"
         "\x9c\x05\x29\x6f\x4b\xcb\x3c\x9a\xb0\x6a\xbe\x19\x67\x96\xc9\x08\xfd"
         "\x54\x9d\x17\xa2\x8c\xda\x5b\x05\x18\xf9\x19\x10\xb3\x31\x38\x69\x80"
         "\x9e\x15\xd4\x10\x12\x89\x37\x7f\xa1\x21\x42\x8b\x9b\x4c\xd4\x40\xf2"
         "\x8c\x50\x6d\xd1\xcc\x47\x21\x30\xca\x34\xbd\xff\xed\x11\xe2\xec\xe1"
         "\x88\xac\x3b\xbf\xd7\xa2\xe6\x06\xde\x20\xa2\xfc\xde\x5b\xd6\xb5\xcc"
         "\x1b\x0f\x7a\xba\xf6\x4f\xc0\x97\x9a\x76",
         180);
  *(uint64_t*)0x20000088 = 0xb4;
  *(uint64_t*)0x20000090 = 0x3ff;
  sprintf((char*)0x20000040, "%020llu", (long long)-1);
  syz_mount_image(0x200000c0, 0x20000000, 0xe063, 1, 0x20000080, 0, 0x20000040,
                  2);
  memcpy((void*)0x20000200, "./file0\000", 8);
  syscall(__NR_mount, 0ul, 0x20000200ul, 0ul, 0x2002000ul, 0ul);
  return 0;
}