// https://syzkaller.appspot.com/bug?id=8f233777106f7963a180dc04bcf7b851743d1236
// 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>

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)

#define sys_memfd_create 319

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(sys_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*)0x20000000, "squashfs\000", 9);
  memcpy((void*)0x20000100, "./file0\000", 8);
  *(uint64_t*)0x20000200 = 0x20010000;
  memcpy(
      (void*)0x20010000,
      "\x68\x73\x71\x73\x07\x00\x00\x00\x91\x1d\x67\x5f\x00\x10\x00\x00\x00\x00"
      "\x00\x00\x01\x00\x0c\x00\xd0\x00\x02\x00\x04\x00\x00\x00\x0f\x01\x00\x00"
      "\x00\x00\x00\x00\x06\x02\x00\x00\x00\x00\x00\x00\xb5\x01\x00\x00\x00\x00"
      "\x00\x00\xee\x01\x00\x00\x00\x00\x00\x00\x99\x00\x00\x00\x00\x00\x00\x00"
      "\x3e\x01\x00\x00\x00\x00\x00\x00\x85\x01\x00\x00\x00\x00\x00\x00\xa3\x01"
      "\x00\x00\x00\x00\x00\x00\x78\xda\x2b\xae\xac\xca\x4e\xcc\xc9\x49\x2d\x2a"
      "\xa6\x1d\x03\x00\x85\x49\x2b\x1f\x78\xda\x2b\xae\xac\xca\x4e\xcc\xc9\x49"
      "\x2d\x2a\x1e\x65\x8c\x32\x46\x19\xa3\x0c\x18\x03\x00\x55\x65\xc4\xa2\x73"
      "\x79\x7a\x6b\x61\x6c\x6c\x65\x72\x73\xa3\x00\x78\xda\x63\x62\x78\xcb\xc8"
      "\xc0\xc0\xc8\x30\x51\x36\x3d\x1e\xc8\x60\x48\x00\xe2\xff\x40\x00\xa4\x18"
      "\x52\x80\x58\x04\x88\x99\x90\xd4\x30\x03\xf9\x25\x48\x6a\xa4\x58\x18\x18"
      "\xa4\x81\x34\x33\xc3\x7f\xb8\x1a\xa0\x10\x03\xc8\x2c\x35\x20\xd6\x2f\xc9"
      "\x2d\xd0\x2f\xae\xac\xd2\xcd\xcc\x4d\x4c\x4f\x4d\x4f\xcd\x33\x31\xb4\x34"
      "\x37\x37\x33\xb6\x34\xd2\x4f\xcb\xcc\x49\x35\x80\x90\x8c\x48\x36\x30\x31"
      "\x40\x00\x88\xd6\x04\x62\x76\x20\xe6\x44\x92\x67\x05\xf2\xfb\xa1\x6a\xb8"
      "\x18\x50\x01\x23\x92\xcb\xa0\xf2\x8c\xc8\x7a\xd9\x80\x62\x33\xa1\x72\x1a"
      "\xca\xa8\x7a\x99\x90\xf4\x22\x9b\x01\x31\xf7\x00\xdc\x0c\x76\xa8\x18\x28"
      "\x24\x42\x80\x7e\xe4\x00\xd2\x00\x8b\x6a\x35\x09\x45\x00\x78\xda\x63\x64"
      "\x80\x00\x66\x20\x56\x01\x62\x26\x06\x16\x86\xb4\xcc\x9c\x54\x03\x0f\x06"
      "\x46\xa0\x20\x84\x63\xc8\x02\x55\xc5\x08\xa5\x99\x18\x38\xc0\x12\x7a\xc9"
      "\xf9\x39\x29\x6d\x40\x61\x46\x98\xb6\x65\x40\x06\xcc\x0c\xc3\x47\x0c\xac"
      "\x70\x8e\x11\x32\xc7\x18\x00\x42\x1f\x11\xfb\x1c\x00\x78\xda\x63\x60\x80"
      "\x80\x36\x28\xad\x02\xa5\x3d\xa0\xf4\x32\x28\xfd\x08\x4a\xab\x31\x42\x68"
      "\x00\x46\xdf\x02\xa2\x85\x01\x00\x00\x00\x00\x00\x00\x08\x80\x5c\xf9\x01"
      "\x00\x53\x5f\x01\x00\xab\x01\x00\x00\x00\x00\x00\x00\x1d\x00\x78\xda\x63"
      "\x60\x60\x63\xa8\x48\x2c\x29\x29\x32\x64\x63\x60\x80\xb2\x18\x60\x62\x46"
      "\x70\x31\x23\x00\xb5\xbc\x09\xab\x10\x80\x00\x00\x00\x00\x00\x00\x00\x00"
      "\x02\x00\x00\x00\x24\x00\x00\x00\xbd\x01\x00\x00\x00\x00\x00\x00\x01",
      503);
  *(uint64_t*)0x20000208 = 0x1f7;
  *(uint64_t*)0x20000210 = 0;
  *(uint8_t*)0x20010200 = 0;
  syz_mount_image(0x20000000, 0x20000100, 0x1000, 5, 0x20000200, 0, 0x20010200);
  return 0;
}