// https://syzkaller.appspot.com/bug?id=424c53bca1b19e6a742443e90e4338427a17ccb3
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.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, long segments)
{
  unsigned long i;
  struct fs_image_segment* segs = (struct fs_image_segment*)segments;
  if (nsegs > IMAGE_MAX_SEGMENTS)
    nsegs = IMAGE_MAX_SEGMENTS;
  for (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 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)
{
  char loopname[64], fs[32], opts[256];
  int loopfd, err = 0, res = -1;
  unsigned long i;

  size = fs_image_segment_check(size, nsegs, segments);
  int memfd = syscall(sys_memfd_create, "syz_mount_image", 0);
  if (memfd == -1) {
    err = errno;
    goto error;
  }
  if (ftruncate(memfd, size)) {
    err = errno;
    goto error_close_memfd;
  }
  for (i = 0; i < nsegs; i++) {
    struct fs_image_segment* segs = (struct fs_image_segment*)segments;
    int res1 = 0;
    res1 = pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset);
    if (res1 < 0) {
    }
  }
  snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid);
  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;
    }
  }
  mkdir((char*)dir, 0777);
  memset(fs, 0, sizeof(fs));
  strncpy(fs, (char*)fsarg, sizeof(fs) - 1);
  memset(opts, 0, sizeof(opts));
  strncpy(opts, (char*)optsarg, 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");
  }
  if (mount(loopname, (char*)dir, fs, flags, opts)) {
    err = errno;
    goto error_clear_loop;
  }
  res = 0;
error_clear_loop:
  ioctl(loopfd, LOOP_CLR_FD, 0);
error_close_loop:
  close(loopfd);
error_close_memfd:
  close(memfd);
error:
  errno = err;
  return res;
}

#ifndef __NR_userfaultfd
#define __NR_userfaultfd 323
#endif

uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff};

int main(void)
{
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0ul);
  intptr_t res = 0;
  memcpy((void*)0x200002c0, "tmpfs\000", 6);
  memcpy((void*)0x20000400, "./bus\000", 6);
  memcpy((void*)0x200005c0, "huge=always", 11);
  syz_mount_image(0x200002c0, 0x20000400, 0, 0, 0, 0, 0x200005c0);
  memcpy((void*)0x200000c0, "./bus/file0\000", 12);
  res = syscall(__NR_creat, 0x200000c0ul, 0ul);
  if (res != -1)
    r[0] = res;
  *(uint8_t*)0x20000540 = 0x7f;
  *(uint8_t*)0x20000541 = 0x45;
  *(uint8_t*)0x20000542 = 0x4c;
  *(uint8_t*)0x20000543 = 0x46;
  *(uint8_t*)0x20000544 = 0;
  *(uint8_t*)0x20000545 = 0;
  *(uint8_t*)0x20000546 = 0;
  *(uint8_t*)0x20000547 = 0;
  *(uint64_t*)0x20000548 = 0;
  *(uint16_t*)0x20000550 = 0;
  *(uint16_t*)0x20000552 = 0;
  *(uint32_t*)0x20000554 = 0;
  *(uint32_t*)0x20000558 = 0;
  *(uint32_t*)0x2000055c = 0x38;
  *(uint32_t*)0x20000560 = 0;
  *(uint32_t*)0x20000564 = 0;
  *(uint16_t*)0x20000568 = 0;
  *(uint16_t*)0x2000056a = 0x20;
  *(uint16_t*)0x2000056c = 0;
  *(uint16_t*)0x2000056e = 0;
  *(uint16_t*)0x20000570 = 0;
  *(uint16_t*)0x20000572 = 0;
  syscall(__NR_write, r[0], 0x20000540ul, 0xfffffdeful);
  syscall(__NR_ftruncate, r[0], 0x1fful);
  syscall(__NR_mmap, 0x20000000ul, 0xfda000ul, 0x1000003ul, 0x4031ul, -1, 0ul);
  res = syscall(__NR_userfaultfd, 0ul);
  if (res != -1)
    r[1] = res;
  *(uint64_t*)0x200000c0 = 0xaa;
  *(uint64_t*)0x200000c8 = 0;
  *(uint64_t*)0x200000d0 = 0;
  syscall(__NR_ioctl, r[1], 0xc018aa3f, 0x200000c0ul);
  *(uint64_t*)0x20000040 = 0x200e2000;
  *(uint64_t*)0x20000048 = 0xc00000;
  *(uint64_t*)0x20000050 = 1;
  *(uint64_t*)0x20000058 = 0;
  syscall(__NR_ioctl, r[1], 0xc020aa00, 0x20000040ul);
  *(uint64_t*)0x200a0fe0 = 0x205e3000;
  *(uint64_t*)0x200a0fe8 = 0x20ce6000;
  *(uint64_t*)0x200a0ff0 = 0x200000;
  *(uint64_t*)0x200a0ff8 = 0;
  syscall(__NR_ioctl, r[1], 0xc028aa03, 0x200a0fe0ul);
  return 0;
}