// https://syzkaller.appspot.com/bug?id=7092911c52535a3189e8b425dfa70d23f1bbc53e
// 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_arp.h>
#include <sched.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_tun.h>
#include <linux/ip.h>
#include <linux/tcp.h>

unsigned long long procid;

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 void vsnprintf_check(char* str, size_t size, const char* format,
                            va_list args)
{
  int rv;
  rv = vsnprintf(str, size, format, args);
  if (rv < 0)
    exit(1);
  if ((size_t)rv >= size)
    exit(1);
}

#define COMMAND_MAX_LEN 128
#define PATH_PREFIX                                                            \
  "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin "
#define PATH_PREFIX_LEN (sizeof(PATH_PREFIX) - 1)

static void execute_command(bool panic, const char* format, ...)
{
  va_list args;
  char command[PATH_PREFIX_LEN + COMMAND_MAX_LEN];
  int rv;
  va_start(args, format);
  memcpy(command, PATH_PREFIX, PATH_PREFIX_LEN);
  vsnprintf_check(command + PATH_PREFIX_LEN, COMMAND_MAX_LEN, format, args);
  va_end(args);
  rv = system(command);
  if (rv) {
    if (panic)
      exit(1);
  }
}

static int tunfd = -1;
static int tun_frags_enabled;
#define SYZ_TUN_MAX_PACKET_SIZE 1000

#define TUN_IFACE "syz_tun"

#define LOCAL_MAC "aa:aa:aa:aa:aa:aa"
#define REMOTE_MAC "aa:aa:aa:aa:aa:bb"

#define LOCAL_IPV4 "172.20.20.170"
#define REMOTE_IPV4 "172.20.20.187"

#define LOCAL_IPV6 "fe80::aa"
#define REMOTE_IPV6 "fe80::bb"

#define IFF_NAPI 0x0010
#define IFF_NAPI_FRAGS 0x0020

static void initialize_tun(void)
{
  tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK);
  if (tunfd == -1) {
    printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n");
    printf("otherwise fuzzing or reproducing might not work as intended\n");
    return;
  }
  const int kTunFd = 240;
  if (dup2(tunfd, kTunFd) < 0)
    exit(1);
  close(tunfd);
  tunfd = kTunFd;
  struct ifreq ifr;
  memset(&ifr, 0, sizeof(ifr));
  strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ);
  ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_NAPI | IFF_NAPI_FRAGS;
  if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) {
    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
    if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0)
      exit(1);
  }
  if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0)
    exit(1);
  tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0;
  execute_command(0, "sysctl -w net.ipv6.conf.%s.accept_dad=0", TUN_IFACE);
  execute_command(0, "sysctl -w net.ipv6.conf.%s.router_solicitations=0",
                  TUN_IFACE);
  execute_command(1, "ip link set dev %s address %s", TUN_IFACE, LOCAL_MAC);
  execute_command(1, "ip addr add %s/24 dev %s", LOCAL_IPV4, TUN_IFACE);
  execute_command(1, "ip neigh add %s lladdr %s dev %s nud permanent",
                  REMOTE_IPV4, REMOTE_MAC, TUN_IFACE);
  execute_command(0, "ip -6 addr add %s/120 dev %s", LOCAL_IPV6, TUN_IFACE);
  execute_command(0, "ip -6 neigh add %s lladdr %s dev %s nud permanent",
                  REMOTE_IPV6, REMOTE_MAC, TUN_IFACE);
  execute_command(1, "ip link set dev %s up", TUN_IFACE);
}

static int read_tun(char* data, int size)
{
  if (tunfd < 0)
    return -1;
  int rv = read(tunfd, data, size);
  if (rv < 0) {
    if (errno == EAGAIN)
      return -1;
    if (errno == EBADFD)
      return -1;
    exit(1);
  }
  return rv;
}

static void flush_tun()
{
  char data[SYZ_TUN_MAX_PACKET_SIZE];
  while (read_tun(&data[0], sizeof(data)) != -1) {
  }
}

static void setup_common()
{
  if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
  }
}

static void loop();

static void sandbox_common()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  setsid();
  struct rlimit rlim;
  rlim.rlim_cur = rlim.rlim_max = 160 << 20;
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 8 << 20;
  setrlimit(RLIMIT_MEMLOCK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 136 << 20;
  setrlimit(RLIMIT_FSIZE, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 1 << 20;
  setrlimit(RLIMIT_STACK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 0;
  setrlimit(RLIMIT_CORE, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 256;
  setrlimit(RLIMIT_NOFILE, &rlim);
  if (unshare(CLONE_NEWNS)) {
  }
  if (unshare(CLONE_NEWIPC)) {
  }
  if (unshare(0x02000000)) {
  }
  if (unshare(CLONE_NEWUTS)) {
  }
  if (unshare(CLONE_SYSVSEM)) {
  }
}

int wait_for_loop(int pid)
{
  if (pid < 0)
    exit(1);
  int status = 0;
  while (waitpid(-1, &status, __WALL) != pid) {
  }
  return WEXITSTATUS(status);
}

static int do_sandbox_none(void)
{
  if (unshare(CLONE_NEWPID)) {
  }
  int pid = fork();
  if (pid != 0)
    return wait_for_loop(pid);
  setup_common();
  sandbox_common();
  if (unshare(CLONE_NEWNET)) {
  }
  initialize_tun();
  loop();
  exit(1);
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir)
{
  DIR* dp;
  struct dirent* ep;
  int iter = 0;
retry:
  while (umount2(dir, MNT_DETACH) == 0) {
  }
  dp = opendir(dir);
  if (dp == NULL) {
    if (errno == EMFILE) {
      exit(1);
    }
    exit(1);
  }
  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) == 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))
        exit(1);
    }
  }
  closedir(dp);
  int i;
  for (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))
          exit(1);
        continue;
      }
      if (errno == ENOTEMPTY) {
        if (iter < 100) {
          iter++;
          goto retry;
        }
      }
    }
    exit(1);
  }
}

static void kill_and_wait(int pid, int* status)
{
  kill(-pid, SIGKILL);
  kill(pid, SIGKILL);
  int i;
  for (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) {
  }
}

#define SYZ_HAVE_SETUP_TEST 1
static void setup_test()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  flush_tun();
}

#define SYZ_HAVE_RESET_TEST 1
static void reset_test()
{
  int fd;
  for (fd = 3; fd < 30; fd++)
    close(fd);
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void)
{
  int iter;
  for (iter = 0;; iter++) {
    char cwdbuf[32];
    sprintf(cwdbuf, "./%d", iter);
    if (mkdir(cwdbuf, 0777))
      exit(1);
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      if (chdir(cwdbuf))
        exit(1);
      setup_test();
      execute_one();
      reset_test();
      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 < 5 * 1000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
    remove_dir(cwdbuf);
  }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_one(void)
{
  long res = 0;
  res = syscall(__NR_socket, 0xa, 2, 0);
  if (res != -1)
    r[0] = res;
  *(uint32_t*)0x20000240 = htobe32(0);
  *(uint8_t*)0x20000250 = 0;
  *(uint8_t*)0x20000251 = 0;
  *(uint8_t*)0x20000252 = 0;
  *(uint8_t*)0x20000253 = 0;
  *(uint8_t*)0x20000254 = 0;
  *(uint8_t*)0x20000255 = 0;
  *(uint8_t*)0x20000256 = 0;
  *(uint8_t*)0x20000257 = 0;
  *(uint8_t*)0x20000258 = 0;
  *(uint8_t*)0x20000259 = 0;
  *(uint8_t*)0x2000025a = -1;
  *(uint8_t*)0x2000025b = -1;
  *(uint32_t*)0x2000025c = htobe32(0);
  *(uint16_t*)0x20000260 = htobe16(0);
  *(uint16_t*)0x20000262 = htobe16(0);
  *(uint16_t*)0x20000264 = htobe16(0);
  *(uint16_t*)0x20000266 = htobe16(0);
  *(uint16_t*)0x20000268 = 0xa;
  *(uint8_t*)0x2000026a = 0;
  *(uint8_t*)0x2000026b = 0;
  *(uint8_t*)0x2000026c = 0;
  *(uint32_t*)0x20000270 = 0;
  *(uint32_t*)0x20000274 = 0;
  *(uint64_t*)0x20000278 = 0;
  *(uint64_t*)0x20000280 = 0;
  *(uint64_t*)0x20000288 = 0;
  *(uint64_t*)0x20000290 = 0;
  *(uint64_t*)0x20000298 = 0;
  *(uint64_t*)0x200002a0 = 0;
  *(uint64_t*)0x200002a8 = 0;
  *(uint64_t*)0x200002b0 = 0;
  *(uint64_t*)0x200002b8 = 0;
  *(uint64_t*)0x200002c0 = 0;
  *(uint64_t*)0x200002c8 = 0;
  *(uint64_t*)0x200002d0 = 0;
  *(uint32_t*)0x200002d8 = 0;
  *(uint32_t*)0x200002dc = 0;
  *(uint8_t*)0x200002e0 = 1;
  *(uint8_t*)0x200002e1 = 0;
  *(uint8_t*)0x200002e2 = 0;
  *(uint8_t*)0x200002e3 = 0;
  *(uint8_t*)0x200002e8 = 0xfe;
  *(uint8_t*)0x200002e9 = 0x80;
  *(uint8_t*)0x200002ea = 0;
  *(uint8_t*)0x200002eb = 0;
  *(uint8_t*)0x200002ec = 0;
  *(uint8_t*)0x200002ed = 0;
  *(uint8_t*)0x200002ee = 0;
  *(uint8_t*)0x200002ef = 0;
  *(uint8_t*)0x200002f0 = 0;
  *(uint8_t*)0x200002f1 = 0;
  *(uint8_t*)0x200002f2 = 0;
  *(uint8_t*)0x200002f3 = 0;
  *(uint8_t*)0x200002f4 = 0;
  *(uint8_t*)0x200002f5 = 0;
  *(uint8_t*)0x200002f6 = 0;
  *(uint8_t*)0x200002f7 = 0xaa;
  *(uint32_t*)0x200002f8 = htobe32(0);
  *(uint8_t*)0x200002fc = 0x32;
  *(uint16_t*)0x20000300 = 0;
  *(uint8_t*)0x20000304 = 0;
  *(uint8_t*)0x20000305 = 0;
  *(uint8_t*)0x20000306 = 0;
  *(uint8_t*)0x20000307 = 0;
  *(uint8_t*)0x20000308 = 0;
  *(uint8_t*)0x20000309 = 0;
  *(uint8_t*)0x2000030a = 0;
  *(uint8_t*)0x2000030b = 0;
  *(uint8_t*)0x2000030c = 0;
  *(uint8_t*)0x2000030d = 0;
  *(uint8_t*)0x2000030e = 0;
  *(uint8_t*)0x2000030f = 0;
  *(uint8_t*)0x20000310 = 0;
  *(uint8_t*)0x20000311 = 0;
  *(uint8_t*)0x20000312 = 0;
  *(uint8_t*)0x20000313 = 0;
  *(uint32_t*)0x20000314 = 0;
  *(uint8_t*)0x20000318 = 5;
  *(uint8_t*)0x20000319 = 0;
  *(uint8_t*)0x2000031a = 0;
  *(uint32_t*)0x2000031c = 0;
  *(uint32_t*)0x20000320 = 0;
  *(uint32_t*)0x20000324 = 0;
  syscall(__NR_setsockopt, r[0], 0x29, 0x23, 0x20000240, 0xe8);
  *(uint16_t*)0x20000540 = 0xa;
  *(uint16_t*)0x20000542 = htobe16(0x4e21);
  *(uint32_t*)0x20000544 = 0x4bb;
  *(uint8_t*)0x20000548 = 0xfe;
  *(uint8_t*)0x20000549 = 0x80;
  *(uint8_t*)0x2000054a = 0;
  *(uint8_t*)0x2000054b = 0;
  *(uint8_t*)0x2000054c = 0;
  *(uint8_t*)0x2000054d = 0;
  *(uint8_t*)0x2000054e = 0;
  *(uint8_t*)0x2000054f = 0;
  *(uint8_t*)0x20000550 = 0;
  *(uint8_t*)0x20000551 = 0;
  *(uint8_t*)0x20000552 = 0;
  *(uint8_t*)0x20000553 = 0;
  *(uint8_t*)0x20000554 = 0;
  *(uint8_t*)0x20000555 = 0;
  *(uint8_t*)0x20000556 = 0;
  *(uint8_t*)0x20000557 = 0xaa;
  *(uint32_t*)0x20000558 = 4;
  syscall(__NR_connect, r[0], 0x20000540, 0x1c);
  memcpy((void*)0x20000200, "./file0", 8);
  syscall(__NR_mkdir, 0x20000200, 0);
  memcpy((void*)0x208deff8, "./file0", 8);
  memcpy((void*)0x20000040, "./file0", 8);
  memcpy((void*)0x2015bffc, "nfs", 4);
  syscall(__NR_mount, 0x208deff8, 0x20000040, 0x2015bffc, 0x7a00, 0x20000000);
  memcpy((void*)0x20000240, "./file0", 8);
  memcpy((void*)0x20000000, "./file0", 8);
  syscall(__NR_pivot_root, 0x20000240, 0x20000000);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 8; procid++) {
    if (fork() == 0) {
      use_temporary_dir();
      do_sandbox_none();
    }
  }
  sleep(1000000);
  return 0;
}