// https://syzkaller.appspot.com/bug?id=4157935be2e32fae6b62aa95bb0a08b07160b986
// 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)
{
  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;
  }

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*)0x20001480, "ntfs3\000", 6);
  memcpy((void*)0x200014c0, "./file0\000", 8);
  *(uint64_t*)0x20002940 = 0;
  *(uint64_t*)0x20002948 = 0;
  *(uint64_t*)0x20002950 = 0xffffffff;
  *(uint64_t*)0x20002958 = 0;
  *(uint64_t*)0x20002960 = 0;
  *(uint64_t*)0x20002968 = 0x40;
  *(uint64_t*)0x20002970 = 0;
  *(uint64_t*)0x20002978 = 0;
  *(uint64_t*)0x20002980 = 9;
  *(uint64_t*)0x20002988 = 0;
  *(uint64_t*)0x20002990 = 0;
  *(uint64_t*)0x20002998 = 1;
  *(uint64_t*)0x200029a0 = 0;
  *(uint64_t*)0x200029a8 = 0;
  *(uint64_t*)0x200029b0 = 0;
  *(uint64_t*)0x200029b8 = 0;
  *(uint64_t*)0x200029c0 = 0;
  *(uint64_t*)0x200029c8 = 0xff;
  *(uint64_t*)0x200029d0 = 0;
  *(uint64_t*)0x200029d8 = 0;
  *(uint64_t*)0x200029e0 = 0x9fd;
  *(uint64_t*)0x200029e8 = 0;
  *(uint64_t*)0x200029f0 = 0;
  *(uint64_t*)0x200029f8 = 0x81;
  memcpy((void*)0x20001280,
         "\x69\x6f\x63\x68\x61\x72\x73\x65\x74\x3d\x63\x70\x38\x36\x33\x2c\x73"
         "\x79\x73\x5f\x69\x6d\x6d\x75\x74\x61\x62\x6c\x65\x2c\x69\x6f\x63\x68"
         "\x76\x72\x73\x65\x74\x3d\x6d\x61\x63\x69\x63\x65\x6c\x61\x6e\x64\x2c"
         "\x70\x6c\x6c\x6f\x63\x2c\x64\x69\x73\x63\x61\x72\x64\x2c\x73\x6d\x61"
         "\x63\x6b\x66\x73\x66\x6c\x6f\x6f\x72\x3d\x2c\x00\x98\x2e\x55\x26\xb7"
         "\x24\x22\xff\x44\xd6\x46\x5d\x61\x0f\xb5\xcc\xa1\x5e\xdb\x1a\xef\xb1"
         "\xc3\x0e\x49\xb1\xb1\x39\x99\x16\x07\x34\xd2\x17\x26\xcb\x13",
         117);
  syz_mount_image(0x20001480, 0x200014c0, 0x101, 8, 0x20002940, 8, 0x20001280);
  return 0;
}