// https://syzkaller.appspot.com/bug?id=04e95388a1b71c0e15b667b54b34ad3a60a9d933
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <arpa/inet.h>
#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <net/if.h>
#include <netinet/in.h>
#include <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#include <linux/genetlink.h>
#include <linux/if_addr.h>
#include <linux/if_link.h>
#include <linux/in6.h>
#include <linux/loop.h>
#include <linux/neighbour.h>
#include <linux/net.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/veth.h>

#ifndef __NR_memfd_create
#define __NR_memfd_create 319
#endif

static unsigned long long procid;

static __thread int clone_ongoing;
static __thread int skip_segv;
static __thread jmp_buf segv_env;

static void segv_handler(int sig, siginfo_t* info, void* ctx)
{
  if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) {
    exit(sig);
  }
  uintptr_t addr = (uintptr_t)info->si_addr;
  const uintptr_t prog_start = 1 << 20;
  const uintptr_t prog_end = 100 << 20;
  int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0;
  int valid = addr < prog_start || addr > prog_end;
  if (skip && valid) {
    _longjmp(segv_env, 1);
  }
  exit(sig);
}

static void install_segv_handler(void)
{
  struct sigaction sa;
  memset(&sa, 0, sizeof(sa));
  sa.sa_handler = SIG_IGN;
  syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8);
  syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8);
  memset(&sa, 0, sizeof(sa));
  sa.sa_sigaction = segv_handler;
  sa.sa_flags = SA_NODEFER | SA_SIGINFO;
  sigaction(SIGSEGV, &sa, NULL);
  sigaction(SIGBUS, &sa, NULL);
}

#define NONFAILING(...)                                                        \
  ({                                                                           \
    int ok = 1;                                                                \
    __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    if (_setjmp(segv_env) == 0) {                                              \
      __VA_ARGS__;                                                             \
    } else                                                                     \
      ok = 0;                                                                  \
    __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    ok;                                                                        \
  })

static void sleep_ms(uint64_t ms)
{
  usleep(ms * 1000);
}

static uint64_t current_time_ms(void)
{
  struct timespec ts;
  if (clock_gettime(CLOCK_MONOTONIC, &ts))
    exit(1);
  return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

static void use_temporary_dir(void)
{
  char tmpdir_template[] = "./syzkaller.XXXXXX";
  char* tmpdir = mkdtemp(tmpdir_template);
  if (!tmpdir)
    exit(1);
  if (chmod(tmpdir, 0777))
    exit(1);
  if (chdir(tmpdir))
    exit(1);
}

static bool write_file(const char* file, const char* what, ...)
{
  char buf[1024];
  va_list args;
  va_start(args, what);
  vsnprintf(buf, sizeof(buf), what, args);
  va_end(args);
  buf[sizeof(buf) - 1] = 0;
  int len = strlen(buf);
  int fd = open(file, O_WRONLY | O_CLOEXEC);
  if (fd == -1)
    return false;
  if (write(fd, buf, len) != len) {
    int err = errno;
    close(fd);
    errno = err;
    return false;
  }
  close(fd);
  return true;
}

struct nlmsg {
  char* pos;
  int nesting;
  struct nlattr* nested[8];
  char buf[4096];
};

static void netlink_init(struct nlmsg* nlmsg, int typ, int flags,
                         const void* data, int size)
{
  memset(nlmsg, 0, sizeof(*nlmsg));
  struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
  hdr->nlmsg_type = typ;
  hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
  memcpy(hdr + 1, data, size);
  nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size);
}

static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data,
                         int size)
{
  struct nlattr* attr = (struct nlattr*)nlmsg->pos;
  attr->nla_len = sizeof(*attr) + size;
  attr->nla_type = typ;
  if (size > 0)
    memcpy(attr + 1, data, size);
  nlmsg->pos += NLMSG_ALIGN(attr->nla_len);
}

static void netlink_nest(struct nlmsg* nlmsg, int typ)
{
  struct nlattr* attr = (struct nlattr*)nlmsg->pos;
  attr->nla_type = typ;
  nlmsg->pos += sizeof(*attr);
  nlmsg->nested[nlmsg->nesting++] = attr;
}

static void netlink_done(struct nlmsg* nlmsg)
{
  struct nlattr* attr = nlmsg->nested[--nlmsg->nesting];
  attr->nla_len = nlmsg->pos - (char*)attr;
}

static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type,
                            int* reply_len, bool dofail)
{
  if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting)
    exit(1);
  struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
  hdr->nlmsg_len = nlmsg->pos - nlmsg->buf;
  struct sockaddr_nl addr;
  memset(&addr, 0, sizeof(addr));
  addr.nl_family = AF_NETLINK;
  ssize_t n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0,
                     (struct sockaddr*)&addr, sizeof(addr));
  if (n != (ssize_t)hdr->nlmsg_len) {
    if (dofail)
      exit(1);
    return -1;
  }
  n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0);
  if (reply_len)
    *reply_len = 0;
  if (n < 0) {
    if (dofail)
      exit(1);
    return -1;
  }
  if (n < (ssize_t)sizeof(struct nlmsghdr)) {
    errno = EINVAL;
    if (dofail)
      exit(1);
    return -1;
  }
  if (hdr->nlmsg_type == NLMSG_DONE)
    return 0;
  if (reply_len && hdr->nlmsg_type == reply_type) {
    *reply_len = n;
    return 0;
  }
  if (n < (ssize_t)(sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))) {
    errno = EINVAL;
    if (dofail)
      exit(1);
    return -1;
  }
  if (hdr->nlmsg_type != NLMSG_ERROR) {
    errno = EINVAL;
    if (dofail)
      exit(1);
    return -1;
  }
  errno = -((struct nlmsgerr*)(hdr + 1))->error;
  return -errno;
}

static int netlink_send(struct nlmsg* nlmsg, int sock)
{
  return netlink_send_ext(nlmsg, sock, 0, NULL, true);
}

static int netlink_query_family_id(struct nlmsg* nlmsg, int sock,
                                   const char* family_name, bool dofail)
{
  struct genlmsghdr genlhdr;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = CTRL_CMD_GETFAMILY;
  netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr));
  netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, family_name,
               strnlen(family_name, GENL_NAMSIZ - 1) + 1);
  int n = 0;
  int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n, dofail);
  if (err < 0) {
    return -1;
  }
  uint16_t id = 0;
  struct nlattr* attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN +
                                         NLMSG_ALIGN(sizeof(genlhdr)));
  for (; (char*)attr < nlmsg->buf + n;
       attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
    if (attr->nla_type == CTRL_ATTR_FAMILY_ID) {
      id = *(uint16_t*)(attr + 1);
      break;
    }
  }
  if (!id) {
    errno = EINVAL;
    return -1;
  }
  recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0);
  return id;
}

static void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type,
                                    const char* name, bool up)
{
  struct ifinfomsg hdr;
  memset(&hdr, 0, sizeof(hdr));
  if (up)
    hdr.ifi_flags = hdr.ifi_change = IFF_UP;
  netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr,
               sizeof(hdr));
  if (name)
    netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name));
  netlink_nest(nlmsg, IFLA_LINKINFO);
  netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type));
}

static void netlink_device_change(struct nlmsg* nlmsg, int sock,
                                  const char* name, bool up, const char* master,
                                  const void* mac, int macsize,
                                  const char* new_name)
{
  struct ifinfomsg hdr;
  memset(&hdr, 0, sizeof(hdr));
  if (up)
    hdr.ifi_flags = hdr.ifi_change = IFF_UP;
  hdr.ifi_index = if_nametoindex(name);
  netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr));
  if (new_name)
    netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name));
  if (master) {
    int ifindex = if_nametoindex(master);
    netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex));
  }
  if (macsize)
    netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize);
  int err = netlink_send(nlmsg, sock);
  if (err < 0) {
  }
}

static struct nlmsg nlmsg;

//% This code is derived from puff.{c,h}, found in the zlib development. The
//% original files come with the following copyright notice:

//% Copyright (C) 2002-2013 Mark Adler, all rights reserved
//% version 2.3, 21 Jan 2013
//% This software is provided 'as-is', without any express or implied
//% warranty.  In no event will the author be held liable for any damages
//% arising from the use of this software.
//% Permission is granted to anyone to use this software for any purpose,
//% including commercial applications, and to alter it and redistribute it
//% freely, subject to the following restrictions:
//% 1. The origin of this software must not be misrepresented; you must not
//%    claim that you wrote the original software. If you use this software
//%    in a product, an acknowledgment in the product documentation would be
//%    appreciated but is not required.
//% 2. Altered source versions must be plainly marked as such, and must not be
//%    misrepresented as being the original software.
//% 3. This notice may not be removed or altered from any source distribution.
//% Mark Adler    madler@alumni.caltech.edu

//% BEGIN CODE DERIVED FROM puff.{c,h}

#define MAXBITS 15
#define MAXLCODES 286
#define MAXDCODES 30
#define MAXCODES (MAXLCODES + MAXDCODES)
#define FIXLCODES 288

struct puff_state {
  unsigned char* out;
  unsigned long outlen;
  unsigned long outcnt;
  const unsigned char* in;
  unsigned long inlen;
  unsigned long incnt;
  int bitbuf;
  int bitcnt;
  jmp_buf env;
};
static int puff_bits(struct puff_state* s, int need)
{
  long val = s->bitbuf;
  while (s->bitcnt < need) {
    if (s->incnt == s->inlen)
      longjmp(s->env, 1);
    val |= (long)(s->in[s->incnt++]) << s->bitcnt;
    s->bitcnt += 8;
  }
  s->bitbuf = (int)(val >> need);
  s->bitcnt -= need;
  return (int)(val & ((1L << need) - 1));
}
static int puff_stored(struct puff_state* s)
{
  s->bitbuf = 0;
  s->bitcnt = 0;
  if (s->incnt + 4 > s->inlen)
    return 2;
  unsigned len = s->in[s->incnt++];
  len |= s->in[s->incnt++] << 8;
  if (s->in[s->incnt++] != (~len & 0xff) ||
      s->in[s->incnt++] != ((~len >> 8) & 0xff))
    return -2;
  if (s->incnt + len > s->inlen)
    return 2;
  if (s->outcnt + len > s->outlen)
    return 1;
  for (; len--; s->outcnt++, s->incnt++) {
    if (s->in[s->incnt])
      s->out[s->outcnt] = s->in[s->incnt];
  }
  return 0;
}
struct puff_huffman {
  short* count;
  short* symbol;
};
static int puff_decode(struct puff_state* s, const struct puff_huffman* h)
{
  int first = 0;
  int index = 0;
  int bitbuf = s->bitbuf;
  int left = s->bitcnt;
  int code = first = index = 0;
  int len = 1;
  short* next = h->count + 1;
  while (1) {
    while (left--) {
      code |= bitbuf & 1;
      bitbuf >>= 1;
      int count = *next++;
      if (code - count < first) {
        s->bitbuf = bitbuf;
        s->bitcnt = (s->bitcnt - len) & 7;
        return h->symbol[index + (code - first)];
      }
      index += count;
      first += count;
      first <<= 1;
      code <<= 1;
      len++;
    }
    left = (MAXBITS + 1) - len;
    if (left == 0)
      break;
    if (s->incnt == s->inlen)
      longjmp(s->env, 1);
    bitbuf = s->in[s->incnt++];
    if (left > 8)
      left = 8;
  }
  return -10;
}
static int puff_construct(struct puff_huffman* h, const short* length, int n)
{
  int len;
  for (len = 0; len <= MAXBITS; len++)
    h->count[len] = 0;
  int symbol;
  for (symbol = 0; symbol < n; symbol++)
    (h->count[length[symbol]])++;
  if (h->count[0] == n)
    return 0;
  int left = 1;
  for (len = 1; len <= MAXBITS; len++) {
    left <<= 1;
    left -= h->count[len];
    if (left < 0)
      return left;
  }
  short offs[MAXBITS + 1];
  offs[1] = 0;
  for (len = 1; len < MAXBITS; len++)
    offs[len + 1] = offs[len] + h->count[len];
  for (symbol = 0; symbol < n; symbol++)
    if (length[symbol] != 0)
      h->symbol[offs[length[symbol]]++] = symbol;
  return left;
}
static int puff_codes(struct puff_state* s, const struct puff_huffman* lencode,
                      const struct puff_huffman* distcode)
{
  static const short lens[29] = {3,  4,  5,  6,   7,   8,   9,   10,  11, 13,
                                 15, 17, 19, 23,  27,  31,  35,  43,  51, 59,
                                 67, 83, 99, 115, 131, 163, 195, 227, 258};
  static const short lext[29] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 2, 2, 2,
                                 2, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 5, 0};
  static const short dists[30] = {
      1,    2,    3,    4,    5,    7,    9,    13,    17,    25,
      33,   49,   65,   97,   129,  193,  257,  385,   513,   769,
      1025, 1537, 2049, 3073, 4097, 6145, 8193, 12289, 16385, 24577};
  static const short dext[30] = {0, 0, 0,  0,  1,  1,  2,  2,  3,  3,
                                 4, 4, 5,  5,  6,  6,  7,  7,  8,  8,
                                 9, 9, 10, 10, 11, 11, 12, 12, 13, 13};
  int symbol;
  do {
    symbol = puff_decode(s, lencode);
    if (symbol < 0)
      return symbol;
    if (symbol < 256) {
      if (s->outcnt == s->outlen)
        return 1;
      if (symbol)
        s->out[s->outcnt] = symbol;
      s->outcnt++;
    } else if (symbol > 256) {
      symbol -= 257;
      if (symbol >= 29)
        return -10;
      int len = lens[symbol] + puff_bits(s, lext[symbol]);
      symbol = puff_decode(s, distcode);
      if (symbol < 0)
        return symbol;
      unsigned dist = dists[symbol] + puff_bits(s, dext[symbol]);
      if (dist > s->outcnt)
        return -11;
      if (s->outcnt + len > s->outlen)
        return 1;
      while (len--) {
        if (dist <= s->outcnt && s->out[s->outcnt - dist])
          s->out[s->outcnt] = s->out[s->outcnt - dist];
        s->outcnt++;
      }
    }
  } while (symbol != 256);
  return 0;
}
static int puff_fixed(struct puff_state* s)
{
  static int virgin = 1;
  static short lencnt[MAXBITS + 1], lensym[FIXLCODES];
  static short distcnt[MAXBITS + 1], distsym[MAXDCODES];
  static struct puff_huffman lencode, distcode;
  if (virgin) {
    lencode.count = lencnt;
    lencode.symbol = lensym;
    distcode.count = distcnt;
    distcode.symbol = distsym;
    short lengths[FIXLCODES];
    int symbol;
    for (symbol = 0; symbol < 144; symbol++)
      lengths[symbol] = 8;
    for (; symbol < 256; symbol++)
      lengths[symbol] = 9;
    for (; symbol < 280; symbol++)
      lengths[symbol] = 7;
    for (; symbol < FIXLCODES; symbol++)
      lengths[symbol] = 8;
    puff_construct(&lencode, lengths, FIXLCODES);
    for (symbol = 0; symbol < MAXDCODES; symbol++)
      lengths[symbol] = 5;
    puff_construct(&distcode, lengths, MAXDCODES);
    virgin = 0;
  }
  return puff_codes(s, &lencode, &distcode);
}
static int puff_dynamic(struct puff_state* s)
{
  static const short order[19] = {16, 17, 18, 0, 8,  7, 9,  6, 10, 5,
                                  11, 4,  12, 3, 13, 2, 14, 1, 15};
  int nlen = puff_bits(s, 5) + 257;
  int ndist = puff_bits(s, 5) + 1;
  int ncode = puff_bits(s, 4) + 4;
  if (nlen > MAXLCODES || ndist > MAXDCODES)
    return -3;
  short lengths[MAXCODES];
  int index;
  for (index = 0; index < ncode; index++)
    lengths[order[index]] = puff_bits(s, 3);
  for (; index < 19; index++)
    lengths[order[index]] = 0;
  short lencnt[MAXBITS + 1], lensym[MAXLCODES];
  struct puff_huffman lencode = {lencnt, lensym};
  int err = puff_construct(&lencode, lengths, 19);
  if (err != 0)
    return -4;
  index = 0;
  while (index < nlen + ndist) {
    int symbol;
    int len;
    symbol = puff_decode(s, &lencode);
    if (symbol < 0)
      return symbol;
    if (symbol < 16)
      lengths[index++] = symbol;
    else {
      len = 0;
      if (symbol == 16) {
        if (index == 0)
          return -5;
        len = lengths[index - 1];
        symbol = 3 + puff_bits(s, 2);
      } else if (symbol == 17)
        symbol = 3 + puff_bits(s, 3);
      else
        symbol = 11 + puff_bits(s, 7);
      if (index + symbol > nlen + ndist)
        return -6;
      while (symbol--)
        lengths[index++] = len;
    }
  }
  if (lengths[256] == 0)
    return -9;
  err = puff_construct(&lencode, lengths, nlen);
  if (err && (err < 0 || nlen != lencode.count[0] + lencode.count[1]))
    return -7;
  short distcnt[MAXBITS + 1], distsym[MAXDCODES];
  struct puff_huffman distcode = {distcnt, distsym};
  err = puff_construct(&distcode, lengths + nlen, ndist);
  if (err && (err < 0 || ndist != distcode.count[0] + distcode.count[1]))
    return -8;
  return puff_codes(s, &lencode, &distcode);
}
static int puff(unsigned char* dest, unsigned long* destlen,
                const unsigned char* source, unsigned long sourcelen)
{
  struct puff_state s = {
      .out = dest,
      .outlen = *destlen,
      .outcnt = 0,
      .in = source,
      .inlen = sourcelen,
      .incnt = 0,
      .bitbuf = 0,
      .bitcnt = 0,
  };
  int err;
  if (setjmp(s.env) != 0)
    err = 2;
  else {
    int last;
    do {
      last = puff_bits(&s, 1);
      int type = puff_bits(&s, 2);
      err = type == 0 ? puff_stored(&s)
                      : (type == 1 ? puff_fixed(&s)
                                   : (type == 2 ? puff_dynamic(&s) : -1));
      if (err != 0)
        break;
    } while (!last);
  }
  *destlen = s.outcnt;
  return err;
}

//% END CODE DERIVED FROM puff.{c,h}

#define ZLIB_HEADER_WIDTH 2

static int puff_zlib_to_file(const unsigned char* source,
                             unsigned long sourcelen, int dest_fd)
{
  if (sourcelen < ZLIB_HEADER_WIDTH)
    return 0;
  source += ZLIB_HEADER_WIDTH;
  sourcelen -= ZLIB_HEADER_WIDTH;
  const unsigned long max_destlen = 132 << 20;
  void* ret = mmap(0, max_destlen, PROT_WRITE | PROT_READ,
                   MAP_PRIVATE | MAP_ANON, -1, 0);
  if (ret == MAP_FAILED)
    return -1;
  unsigned char* dest = (unsigned char*)ret;
  unsigned long destlen = max_destlen;
  int err = puff(dest, &destlen, source, sourcelen);
  if (err) {
    munmap(dest, max_destlen);
    errno = -err;
    return -1;
  }
  if (write(dest_fd, dest, destlen) != (ssize_t)destlen) {
    munmap(dest, max_destlen);
    return -1;
  }
  return munmap(dest, destlen);
}

static int setup_loop_device(unsigned char* data, unsigned long size,
                             const char* loopname, int* loopfd_p)
{
  int err = 0, loopfd = -1;
  int memfd = syscall(__NR_memfd_create, "syzkaller", 0);
  if (memfd == -1) {
    err = errno;
    goto error;
  }
  if (puff_zlib_to_file(data, size, memfd)) {
    err = errno;
    goto error_close_memfd;
  }
  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;
    }
  }
  close(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 long flags, volatile long optsarg,
                            volatile long change_dir,
                            volatile unsigned long size, volatile long image)
{
  unsigned char* data = (unsigned char*)image;
  int res = -1, err = 0, loopfd = -1, need_loop_device = !!size;
  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(data, size, loopname, &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) {
    bool has_remount_ro = false;
    char* remount_ro_start = strstr(opts, "errors=remount-ro");
    if (remount_ro_start != NULL) {
      char after = *(remount_ro_start + strlen("errors=remount-ro"));
      char before = remount_ro_start == opts ? '\0' : *(remount_ro_start - 1);
      has_remount_ro = ((before == '\0' || before == ',') &&
                        (after == '\0' || after == ','));
    }
    if (strstr(opts, "errors=panic") || !has_remount_ro)
      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);
  }
  errno = err;
  return res;
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir)
{
  int iter = 0;
  DIR* dp = 0;
retry:
  while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
  }
  dp = opendir(dir);
  if (dp == NULL) {
    if (errno == EMFILE) {
      exit(1);
    }
    exit(1);
  }
  struct dirent* ep = 0;
  while ((ep = readdir(dp))) {
    if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0)
      continue;
    char filename[FILENAME_MAX];
    snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name);
    while (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
    }
    struct stat st;
    if (lstat(filename, &st))
      exit(1);
    if (S_ISDIR(st.st_mode)) {
      remove_dir(filename);
      continue;
    }
    int i;
    for (i = 0;; i++) {
      if (unlink(filename) == 0)
        break;
      if (errno == EPERM) {
        int fd = open(filename, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
          }
          close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno != EBUSY || i > 100)
        exit(1);
      if (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW))
        exit(1);
    }
  }
  closedir(dp);
  for (int i = 0;; i++) {
    if (rmdir(dir) == 0)
      break;
    if (i < 100) {
      if (errno == EPERM) {
        int fd = open(dir, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
          }
          close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno == EBUSY) {
        if (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW))
          exit(1);
        continue;
      }
      if (errno == ENOTEMPTY) {
        if (iter < 100) {
          iter++;
          goto retry;
        }
      }
    }
    exit(1);
  }
}

static int inject_fault(int nth)
{
  int fd;
  fd = open("/proc/thread-self/fail-nth", O_RDWR);
  if (fd == -1)
    exit(1);
  char buf[16];
  sprintf(buf, "%d", nth);
  if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf))
    exit(1);
  return fd;
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  for (int i = 0; i < 100; i++) {
    if (waitpid(-1, status, WNOHANG | __WALL) == pid)
      return;
    usleep(1000);
  }
  DIR* dir = opendir("/sys/fs/fuse/connections");
  if (dir) {
    for (;;) {
      struct dirent* ent = readdir(dir);
      if (!ent)
        break;
      if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
        continue;
      char abort[300];
      snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
               ent->d_name);
      int fd = open(abort, O_WRONLY);
      if (fd == -1) {
        continue;
      }
      if (write(fd, abort, 1) < 0) {
      }
      close(fd);
    }
    closedir(dir);
  } else {
  }
  while (waitpid(-1, status, __WALL) != pid) {
  }
}

static void reset_loop()
{
  char buf[64];
  snprintf(buf, sizeof(buf), "/dev/loop%llu", procid);
  int loopfd = open(buf, O_RDWR);
  if (loopfd != -1) {
    ioctl(loopfd, LOOP_CLR_FD, 0);
    close(loopfd);
  }
}

static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  write_file("/proc/self/oom_score_adj", "1000");
  if (symlink("/dev/binderfs", "./binderfs")) {
  }
}

static void setup_fault()
{
  static struct {
    const char* file;
    const char* val;
    bool fatal;
  } files[] = {
      {"/sys/kernel/debug/failslab/ignore-gfp-wait", "N", true},
      {"/sys/kernel/debug/fail_futex/ignore-private", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-highmem", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/ignore-gfp-wait", "N", false},
      {"/sys/kernel/debug/fail_page_alloc/min-order", "0", false},
  };
  unsigned i;
  for (i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].file, files[i].val)) {
      if (files[i].fatal)
        exit(1);
    }
  }
}

static void setup_sysctl()
{
  char mypid[32];
  snprintf(mypid, sizeof(mypid), "%d", getpid());
  struct {
    const char* name;
    const char* data;
  } files[] = {
      {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"},
      {"/proc/sys/kernel/hung_task_check_interval_secs", "20"},
      {"/proc/sys/net/core/bpf_jit_kallsyms", "1"},
      {"/proc/sys/net/core/bpf_jit_harden", "0"},
      {"/proc/sys/kernel/kptr_restrict", "0"},
      {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"},
      {"/proc/sys/fs/mount-max", "100"},
      {"/proc/sys/vm/oom_dump_tasks", "0"},
      {"/proc/sys/debug/exception-trace", "0"},
      {"/proc/sys/kernel/printk", "7 4 1 3"},
      {"/proc/sys/kernel/keys/gc_delay", "1"},
      {"/proc/sys/vm/oom_kill_allocating_task", "1"},
      {"/proc/sys/kernel/ctrl-alt-del", "0"},
      {"/proc/sys/kernel/cad_pid", mypid},
  };
  for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].name, files[i].data))
      printf("write to %s failed: %s\n", files[i].name, strerror(errno));
  }
}

#define NL802154_CMD_SET_SHORT_ADDR 11
#define NL802154_ATTR_IFINDEX 3
#define NL802154_ATTR_SHORT_ADDR 10

static void setup_802154()
{
  int sock_route = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
  if (sock_route == -1)
    exit(1);
  int sock_generic = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
  if (sock_generic < 0)
    exit(1);
  int nl802154_family_id =
      netlink_query_family_id(&nlmsg, sock_generic, "nl802154", true);
  for (int i = 0; i < 2; i++) {
    char devname[] = "wpan0";
    devname[strlen(devname) - 1] += i;
    uint64_t hwaddr = 0xaaaaaaaaaaaa0002 + (i << 8);
    uint16_t shortaddr = 0xaaa0 + i;
    int ifindex = if_nametoindex(devname);
    struct genlmsghdr genlhdr;
    memset(&genlhdr, 0, sizeof(genlhdr));
    genlhdr.cmd = NL802154_CMD_SET_SHORT_ADDR;
    netlink_init(&nlmsg, nl802154_family_id, 0, &genlhdr, sizeof(genlhdr));
    netlink_attr(&nlmsg, NL802154_ATTR_IFINDEX, &ifindex, sizeof(ifindex));
    netlink_attr(&nlmsg, NL802154_ATTR_SHORT_ADDR, &shortaddr,
                 sizeof(shortaddr));
    int err = netlink_send(&nlmsg, sock_generic);
    if (err < 0) {
    }
    netlink_device_change(&nlmsg, sock_route, devname, true, 0, &hwaddr,
                          sizeof(hwaddr), 0);
    if (i == 0) {
      netlink_add_device_impl(&nlmsg, "lowpan", "lowpan0", false);
      netlink_done(&nlmsg);
      netlink_attr(&nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
      int err = netlink_send(&nlmsg, sock_route);
      if (err < 0) {
      }
    }
  }
  close(sock_route);
  close(sock_generic);
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter = 0;
  for (;; iter++) {
    char cwdbuf[32];
    sprintf(cwdbuf, "./%d", iter);
    if (mkdir(cwdbuf, 0777))
      exit(1);
    reset_loop();
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      if (chdir(cwdbuf))
        exit(1);
      setup_test();
      execute_one();
      exit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      sleep_ms(1);
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
    remove_dir(cwdbuf);
  }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_one(void)
{
  intptr_t res = 0;
  NONFAILING(memcpy((void*)0x20000240, "hfs\000", 4));
  NONFAILING(memcpy((void*)0x20000280, "./file0\000", 8));
  NONFAILING(memcpy(
      (void*)0x20000600,
      "\x78\x9c\xec\xdd\x4f\x6b\x13\x41\x18\xc7\xf1\xdf\x4c\xa3\xae\x5a\xea\xf6"
      "\x8f\x08\xe2\xa9\x5a\xf0\x24\x6d\xbd\x88\x17\x41\xf2\x22\x3c\x89\xda\x44"
      "\x28\x2e\x15\xb4\x82\x7a\xaa\x9e\xc5\x17\xe0\xdd\xb7\xe0\x8b\xf0\x24\xbe"
      "\x01\x3d\x79\xf2\x05\xe4\xb6\x32\xb3\x13\xb3\x4d\x77\xb3\x31\x98\x4c\xdb"
      "\x7c\x3f\x90\x65\x9b\x9d\x67\xf6\x99\xee\x6c\x77\x9e\x40\x89\x00\xcc\xad"
      "\xfb\xed\x1f\x9f\x6f\xff\x72\x2f\x23\x2d\x68\x41\xd2\x5d\xc9\x4a\x4a\xa4"
      "\x96\xa4\xcb\xba\x92\xbc\xda\xdb\xdf\xdd\xcf\xba\x9d\x51\x1d\x2d\xf8\x08"
      "\xf7\x32\x2a\x22\xcd\x91\x36\x3b\x7b\xdd\xaa\x50\x17\xe7\x23\x82\xd4\xfd"
      "\xd4\xd2\x62\xf9\x3d\x4c\x47\x92\xe7\xf9\xcf\xd8\x49\x20\x3a\x7f\xf7\x57"
      "\xb0\xd2\xb9\x70\x77\xfa\xe3\xc9\xcc\x33\x9b\x8e\x83\xd8\x09\x44\x66\x7a"
      "\xea\xe9\xb5\x96\x62\xe7\x01\x00\x88\x2b\x3c\xff\x6d\x78\xce\x2f\x86\xf5"
      "\xbb\xb5\xd2\x46\x78\xec\x9f\xaa\xe7\x7f\x2f\x76\x02\x91\x95\x9e\xff\xbe"
      "\xca\xca\x8d\xbb\xbe\x97\xfc\xa1\x41\xbd\xe7\x4b\x38\x77\xdc\xf6\xab\xc4"
      "\x49\xce\x75\x56\xc5\xcc\x3a\xb4\xc0\x34\x4d\x55\xa5\xcf\xc5\x9e\x7f\xba"
      "\x9b\x75\x6f\xed\x3c\xcf\x3a\x56\xef\x75\x2f\x28\x35\x5b\xf3\xdb\x4e\x31"
      "\x75\xfb\xca\xd9\xbe\x3b\xda\xf5\x7a\x45\x6d\x3a\xc2\xe4\x63\xbf\xe8\xc7"
      "\x70\xc6\x8d\x61\xbb\x26\xff\xd5\xff\x7b\xc6\x66\xe6\xab\xf9\x66\x1e\x9a"
      "\x54\x9f\xd4\xf9\xbb\xfe\x6b\xe5\xc6\x5d\x26\x7f\xa5\xd2\xa1\x2b\x55\xe4"
      "\xbf\x59\xdf\xa3\x1f\x65\x5a\xb4\xaa\x19\xe5\xb2\x3f\xc9\xd5\x70\x86\xa0"
      "\x61\x94\x49\x75\x45\xa2\xfe\x8c\x5a\xd6\xe1\x0f\x08\xd2\xa6\x3c\x7d\xd4"
      "\xca\x50\x54\x31\xba\xad\x86\xa8\xd5\xca\xa8\xed\x86\xa8\xb5\xe1\xa8\xc1"
      "\x6c\xae\x8f\x9c\x36\xf3\xd1\x3c\x30\xeb\xfa\xad\x2f\x6a\x97\xd6\xff\xd6"
      "\xfd\xb6\x37\x34\xce\x9d\xe9\xda\xf8\x96\x61\x66\x8c\x1c\x4f\xcb\xb7\x4c"
      "\xcb\x6f\x1d\x5c\xab\x6c\x69\xff\x7d\x2c\x98\xd8\x07\x3d\xd1\x1d\x2d\xbd"
      "\x7c\xf3\xf6\xd9\xe3\x2c\xeb\xbe\x60\x67\x8e\x76\xfa\x93\xe0\xb8\xe4\xc3"
      "\xce\xf1\xdb\x89\xfb\xe7\x09\xb3\x31\xb8\xe8\xb1\x33\x41\x24\x6e\xdd\x65"
      "\x8a\xfa\xaf\x54\xaf\x6c\xfa\x12\xc9\x6d\xd2\x11\xeb\xf4\xbc\xa9\xf3\x52"
      "\x8f\x5b\x35\xb5\xc1\x8a\xdf\x5e\xa8\xaf\xe0\x2a\xbb\xad\xad\xe0\xc6\xad"
      "\xb9\xae\xdf\x94\x6e\x8c\x7f\xc6\x34\xe4\x79\x4a\x98\xb6\xbe\xeb\x11\x9f"
      "\xff\x03\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x9c\x34"
      "\xb3\xf8\x77\x82\xd8\x63\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
      "\x00\x00\x00\x00\x00\xe0\xa4\xe3\xfb\x7f\x81\xf9\xf5\x27\x00\x00\xff\xff"
      "\xb8\xaf\x7e\xc9",
      580));
  NONFAILING(syz_mount_image(0x20000240, 0x20000280, 0x4000, 0x20000000, 2,
                             0x244, 0x20000600));
  NONFAILING(memcpy((void*)0x20000380, "./file1\000", 8));
  res = syscall(__NR_openat, 0xffffff9c, 0x20000380ul, 0x141842ul, 0ul);
  if (res != -1)
    r[0] = res;
  NONFAILING(memcpy(
      (void*)0x20004200,
      "\x74\xef\xc4\xc4\x19\xfd\xb8\xd6\x6b\x12\xa7\xbb\xf3\x71\xd0\x56\xad\x6f"
      "\x01\xe9\x76\x2d\x70\x40\x1d\x1c\x9d\x33\x1b\x48\xb9\x25\xe9\xe6\xa7\x75"
      "\x9a\xbb\x20\x6b\x9b\x18\xbf\xc3\xf3\xf9\x6a\xdb\x2b\x37\xc2\x12\x1e\xf2"
      "\x1e\x91\xba\xc7\x68\xdd\x33\xdf\x29\x64\x9d\xa1\xd8\x2e\x82\x6a\x55\xc4"
      "\xd6\x20\xb6\xf5\x10\xda\xee\x26\x00\x4b\x74\x1c\x95\x1d\x52\x8d\x80\x6e"
      "\xfb\xe0\x0c\x43\x9f\x2d\xf4\x6d\x3a\xdf\x8b\xe2\x4e\x28\x0b\x94\x8a\x49"
      "\xaf\xd1\x7d\x56\x43\x7c\x6e\x75\x2d\x84\xf9\x9b\xf3\x7a\x88\xf0\xc5\x44"
      "\x88\xdd\x13\xb8\x48\xf2\x38\x1d\x7d\x2a\xec\xb6\x8e\xd1\x67\x62\xe4\xa3"
      "\xc1\xa8\x47\x56\x53\x64\xb9\xf1\xaf\x92\xc9\xc8\x9e\x06\xe8\x9f\xe6\x17"
      "\x9c\xb7\x07\x8a\x74\x2c\xb9\x68\xa9\xf0\x9c\xc6\x90\xdc\x47\x3d\xf2\x9d"
      "\x6a\xd9\xaf\x58\x79\xe9\xa2\x61\x8c\x63\x70\x21\x17\xa3\xa6\x3d\x3a\x42"
      "\x36\xba\xee\x86\xf5\xf4\x52\xe9\x66\x3a\x79\x53\x06\xda\xbb\x97\xdb\x88"
      "\x43\x48\xab\x43\x7b\xdc\x13\xb7\xcf\xb0\x3e\xff\x1c\xf2\x16\xf0\x9d\x21"
      "\x07\x8e\x18\x52\xfc\x7c\x96\x41\x3d\x9d\x65\xc5\x2c\xe9\xba\xa6\xbc\x26"
      "\xde\x7f\x02\x87\x38\xa1\x71\x20\xde\x30\xa4\x33\xc9\xc3\xc8\xe2\x76\xf3"
      "\xae\x5e\x18\xa1\xf9\x57\x67\xff\xfe\x8e\x98\xb0\xc3\xf1\x34\xf1\x22\x63"
      "\xb0\x1c\x36\x86\x6d\x4e\x0e\x85\x6c\xc1\x4e\xcf\x50\x27\x9a\xdb\x94\x38"
      "\xc6\x21\x9c\x49\xca\xe9\x73\xd8\xe7\xfa\xf3\x3d\xcd\xeb\x96\xd7\xef\x7e"
      "\x89\xae\x82\x8c\xb9\x1d\xf2\x29\x39\x30\x7b\xb1\xf7\xfb\x73\x92\xe1\xe2"
      "\x4f\x6b\x63\x16\x6b\x89\x93\x7c\x00\xeb\x8f\xea\x02\x45\xcd\x93\xe4\xaa"
      "\x80\x31\x60\xbd\x71\xc1\xa0\xbb\xb6\xb8\x28\x5d\x8a\xb6\x54\x48\x5a\xb9"
      "\x85\xf1\xdd\x2e\xb9\xab\xf5\x31\x31\xa9\x68\x0d\xca\xfe\x40\x00\xd3\xea"
      "\x52\x8d\xd5\x2a\xba\x3e\x4f\xf6\xa3\x88\x3e\xc6\x14\x25\x3d\x56\x27\xbd"
      "\x91\x52\x2d\x88\x11\x28\x32\x8e\xd1\xe0\x09\x07\xfa\x6c\xc4\x8c\xec\x52"
      "\x68\xbb\xed\xd8\x5e\xc0\x2d\x8b\xac\x31\x83\x46\x0d\xd1\xa2\x7f\xbc\x06"
      "\xb5\x64\x24\x73\xa4\x1a\x6c\xbf\xb0\x7f\x53\xde\xab\x24\x73\xb3\x7c\x3d"
      "\x10\xa1\x25\xd6\x10\xf1\xb9\xea\x5c\x83\xe7\xd4\x62\x04\x8f\x25\xfc\x1e"
      "\x79\x29\x5e\xef\xf7\x50\xa2\x3f\xaf\x5d\x54\x27\x58\xc4\x21\xbb\x06\x73"
      "\x50\x4c\x9d\xba\xe2\x95\x9f\x77",
      512));
  inject_fault(13);
  syscall(__NR_write, r[0], 0x20004200ul, 0xffe00ul);
}
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);
  setup_sysctl();
  setup_fault();
  setup_802154();
  install_segv_handler();
  use_temporary_dir();
  loop();
  return 0;
}