// https://syzkaller.appspot.com/bug?id=68b3528dc42805d2128b6c5620d74fe87c3bfbdf
// 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;
};

#define IMAGE_MAX_SEGMENTS 4096
#define IMAGE_MAX_SIZE (129 << 20)

static unsigned long fs_image_segment_check(unsigned long size,
                                            unsigned long nsegs,
                                            struct fs_image_segment* segs)
{
  if (nsegs > IMAGE_MAX_SEGMENTS)
    nsegs = IMAGE_MAX_SEGMENTS;
  for (size_t i = 0; i < nsegs; i++) {
    if (segs[i].size > IMAGE_MAX_SIZE)
      segs[i].size = IMAGE_MAX_SIZE;
    segs[i].offset %= IMAGE_MAX_SIZE;
    if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size)
      segs[i].offset = IMAGE_MAX_SIZE - segs[i].size;
    if (size < segs[i].offset + segs[i].offset)
      size = segs[i].offset + segs[i].offset;
  }
  if (size > IMAGE_MAX_SIZE)
    size = IMAGE_MAX_SIZE;
  return size;
}
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;
  size = fs_image_segment_check(size, nsegs, segs);
  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*)0x20000000, "gfs2\000", 5);
  memcpy((void*)0x20000100, "./file0\000", 8);
  *(uint64_t*)0x20000040 = 0x20000340;
  memcpy(
      (void*)0x20000340,
      "\x01\x16\x19\x70\x00\x00\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
      "\x00\x64\x00\x00\x00\x00\x00\x00\x07\x09\x00\x00\x07\x6c\x00\x00\x00\x00"
      "\x00\x00\x10\x00\x00\x00\x00\x0c\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
      "\x00\x02\x00\x00\x00\x00\x00\x00\x08\xd0\xb3\x60\x7b\x4f\x84\x5e\xdd\xf4"
      "\x2d\xe8\x69\xba\xa5\x59\x42\xf1\xdc\xca\x83\x30\x10\xa8\x2d\xfa\x5a\xe1"
      "\x4f\xbe\xe4\x8c\xde\xff\x1c\x7f\x8d\xf8\x8c\xb4\x99\xdc\xf2\x1e\x93\xe9"
      "\xa6\x98\xff\x5a\x9f\x58\x80\x05\xf3\x8d\x62\xf0\x7d\x40\x1c\x6a\xce\x70"
      "\xac\xfd\xf6\x2a\xba\xd0\xe2\xf8\xcf\x94\x4e\x9c\x3b\x37\xd6\xd0\x14\x1a"
      "\x88\x7a\xa4\x3f\x1b\xdf\x38\x8f\x69\xd8\xfd\x3f\x74\x5d\x14\x6a\xdd\xd8"
      "\x60\xdb\x0f\xd7\x4f\xc4\xae\x55\xa5\x2c\x21\x2e\x92\x10\x5a\x89\xc0\x09"
      "\x27\xe3\x42\x79\x9b\x57\x37\x32\xc7\x1e\xaa\x7f\xe4\xd2\x20\xf5\x54\xe0"
      "\x6c\xc0\x79\xa2\x8e\x6e\x25\x73\x27\x3a\xdc\x0b\x27\xde\x47\xe0\xad\x3d"
      "\x2c\x98\x2f\xd5\xc6\xa0\xcf\x9d\xaf\xc1\xf6\xe3\x8c\xc3\x3d\x1b\x8b\xe8"
      "\x4e\xe0\x1a\x42\x7e\x55\x87\x42\x16\xda\x6b\x65\x62\x7c\x0c\xaf\xc2\x4b"
      "\x52\xf9\x31\x96\xd9\x4c\x00\x24\xce\xdd\x9c\x25\x5b\x64\x22\x82\x27\x63"
      "\x03\x5b\x4a\x37\x36\x05\x81\x9f\xf9\xe8\x7a\xe2\x0e\x46\x7c\x5b\xdb\xe3"
      "\xd9\x68\xed\x98\xe6\x8c\xe6\x7e\xfd\x37\x94\x8e\xe2\x04\xf0\xdb\xbf\xf1"
      "\x29\x01\xef\x23\x97\x23\xf9\x5a\x51\xd1\x07\x50\xea\x89\xf1\x97\x2f\xed"
      "\xeb\x02\x6a\x82\x7a\xca\xa3\x7f\x0a\xcd\x08\x3b\xff\xf2\xeb\x1a\xf9\xde"
      "\x7d",
      343);
  *(uint64_t*)0x20000048 = 0x157;
  *(uint64_t*)0x20000050 = 0x10000;
  *(uint64_t*)0x20000058 = 0x20000140;
  memcpy((void*)0x20000140,
         "\x60\x22\xa7\xf3\x72\xec\x34\xf6\x34\x52\xc2\x6b\xb0\xbf\xce\x99\xad"
         "\x3e\x09\x83\x25\xdf\xc0\xa4\x97\x4f\x37\xe3\x6e\xf4\x15\xf4\x41\x5b"
         "\x6f\xde\xff\xb3\x27\xe6\x63\x75\x43\xdd\xc1\x87\x02\xf5\x37\x02\xb3"
         "\x00\xea\x66\xa8\x55\x5f\xd5\x2b\x6f\x80\x99\xc8\x4e\x4e\x96\x03\x46"
         "\xea\xd1\xd3\x67\x7f\x38\xce\x9e\x9c\xee\x9b\x77\x1e\xf9\x6d\x85\xcc"
         "\x74\x6e\x90\x28\xc6\x65\x3c\x77\xcc\x4f\x7b\x22\xd2\x3d\x69\x7d\x22"
         "\x60\x8f\xfe\x30\x01\x1f\x82\xac\xf1\xae\x10\x34\x61\xe7\x8b\x43\xa3"
         "\xdd\x68\x84\x80\x0f\x82\x29\xda\xb8\xd4\x6c",
         130);
  *(uint64_t*)0x20000060 = 0x82;
  *(uint64_t*)0x20000068 = 9;
  syz_mount_image(0x20000000, 0x20000100, 4, 2, 0x20000040, 8, 0x20000240, 0);
  return 0;
}