// https://syzkaller.appspot.com/bug?id=9421798588af25c43328bcb82aecf6bbb1f87d37
// 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, "erofs\000", 6);
  memcpy((void*)0x20000080, "./file0\000", 8);
  *(uint64_t*)0x20000200 = 0x20010000;
  memcpy((void*)0x20010000,
         "\xe2\xe1\xf5\xe0\xea\x02\x74\x4a\x01\x00\x00\x00\x0c\x00\x24", 15);
  *(uint64_t*)0x20000208 = 0xf;
  *(uint64_t*)0x20000210 = 0x400;
  *(uint64_t*)0x20000218 = 0x20001280;
  memcpy(
      (void*)0x20001280,
      "\x05\x00\x10\x00\xc0\x41\xcb\x69\x72\xa7\x79\xbb\x85\xb0\xc4\x46\x48\x10"
      "\x99\xc7\xdd\xa9\x0c\x0a\x49\x20\xb5\x8d\x7a\x5c\xbe\x80\x00\xf8\x5f\x50"
      "\x5b\xf0\xff\x92\xe3\x06\x57\x15\x53\x40\x00\x00\x00\x00\x00\x00\xb6\xf8"
      "\xbf\x62\xe7\x19\x7f\x58\xc7\xbe\xbd\x8e\xa5\x33\x27\x77\x9d\xbb\xfb\x83"
      "\x6b\x30\xdb\x29\xb6\x10\x43\x9c\x75\x62\x92\xa2\xde\x4f\x10\xda\xe1\x00"
      "\xa9\xd9\xfe\xc9\xae\x3f\x6f\x8d\xc2\x59\xee\x07\x7f\xd0\x76\xf8\x5d\xb0"
      "\xd2\xa2\x6a\xa9\xaa\xf1\xca\xa5\x95\xc4\x4b\x9a\x9b\x91\x59\x50\x98\xfa"
      "\x71\x59\x7f\x59\xe5\x92\xfb\xd8\x63\x3d\x21\x72\xf4\xee\xa1\x57\x51\xf5"
      "\x76\x25\x83\xf6\xcc\x09\xbb\xca\x33\x87\x0b\xd0\x33\x34\xea\x4b\x5f\x71"
      "\x80\x0e\xcc\xce\xf8\xe8\x0c\xb3\x56\xbb\xc1\xb8\xad\xc4\x61\xe9\x48\x1a"
      "\x05\x9f\xe8\x43\x5c\x83\xec\x0f\x7c\xfd\x3f\x7d\x68\xa1\x74\x31\x94\xd2"
      "\x51\x0e\x9f\x93\xe1\x61\x06\x06\x4a\x66\x75\x96\xd4\x0d\xd2\xf4\x98\x1d"
      "\xaa\x3f\xb1\x48\x62\xa5\x82\x81\xb1\xc2\x5c\x04\x23\x61\x9c\x28\x10\x26"
      "\x69\x86\x71\x7f\x7a\x43\xc1\x1a\xb3\x86\xee\xb6\x03\xbd\x29\x9a\xca\x24"
      "\x2f\x58\x1f\x45\x23\x2e\xb9\x0f\x92\x38\xfc\x16\x58\x3c\xd8\x34\x7b\x43"
      "\xc5\x7a\x3f\x29\x19\xab\x24\xa7\xb7\x54\xc2\x8f\x36\x01\xc3\xb7\x11\x7c"
      "\x25\xc8\x1f",
      291);
  *(uint64_t*)0x20000220 = 0x123;
  *(uint64_t*)0x20000228 = 0x480;
  *(uint64_t*)0x20000230 = 0;
  *(uint64_t*)0x20000238 = 0;
  *(uint64_t*)0x20000240 = 0x1000;
  *(uint8_t*)0x20000040 = 0;
  syz_mount_image(0x20000000, 0x20000080, 0, 3, 0x20000200, 0, 0x20000040);
  memcpy((void*)0x200000c0, "./file0\000", 8);
  syscall(__NR_listxattr, 0x200000c0ul, 0ul, 0ul);
  return 0;
}