// https://syzkaller.appspot.com/bug?id=ef0179626fa1d02db03cd04dde6b57dae3d337a9
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.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/capability.h>

static 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 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;
}

#define MAX_FDS 30

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 = (200 << 20);
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 32 << 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)) {
  }
  typedef struct {
    const char* name;
    const char* value;
  } sysctl_t;
  static const sysctl_t sysctls[] = {
      {"/proc/sys/kernel/shmmax", "16777216"},
      {"/proc/sys/kernel/shmall", "536870912"},
      {"/proc/sys/kernel/shmmni", "1024"},
      {"/proc/sys/kernel/msgmax", "8192"},
      {"/proc/sys/kernel/msgmni", "1024"},
      {"/proc/sys/kernel/msgmnb", "1024"},
      {"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
  };
  unsigned i;
  for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
    write_file(sysctls[i].name, sysctls[i].value);
}

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

static void drop_caps(void)
{
  struct __user_cap_header_struct cap_hdr = {};
  struct __user_cap_data_struct cap_data[2] = {};
  cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
  cap_hdr.pid = getpid();
  if (syscall(SYS_capget, &cap_hdr, &cap_data))
    exit(1);
  const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
  cap_data[0].effective &= ~drop;
  cap_data[0].permitted &= ~drop;
  cap_data[0].inheritable &= ~drop;
  if (syscall(SYS_capset, &cap_hdr, &cap_data))
    exit(1);
}

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();
  drop_caps();
  if (unshare(CLONE_NEWNET)) {
  }
  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:
  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);
    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);
    }
  }
  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) {
        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) {
  }
}

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

static void close_fds()
{
  int fd;
  for (fd = 3; fd < MAX_FDS; 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();
      close_fds();
      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)
{
  intptr_t res = 0;
  memcpy((void*)0x20000000, "./file0\000", 8);
  syscall(__NR_mkdir, 0x20000000ul, 0ul);
  memcpy((void*)0x200000c0, "./file0\000", 8);
  syscall(__NR_mount, 0x20000000ul, 0x200000c0ul, 0ul, 0x2001001ul, 0ul);
  syscall(__NR_setsockopt, -1, 0x114ul, 8ul, 0ul, 0ul);
  memcpy((void*)0x20000140, "./file0\000", 8);
  memcpy((void*)0x20000100, "./file0\000", 8);
  syscall(__NR_pivot_root, 0x20000140ul, 0x20000100ul);
  res = syscall(__NR_socket, 0xful, 3ul, 2ul);
  if (res != -1)
    r[0] = res;
  *(uint64_t*)0x20000180 = 0;
  *(uint32_t*)0x20000188 = 0;
  *(uint64_t*)0x20000190 = 0x20000040;
  *(uint64_t*)0x20000040 = 0;
  *(uint64_t*)0x20000048 = 0;
  *(uint64_t*)0x20000198 = 1;
  *(uint64_t*)0x200001a0 = 0;
  *(uint64_t*)0x200001a8 = 0;
  *(uint32_t*)0x200001b0 = 0;
  syscall(__NR_sendmsg, -1, 0x20000180ul, 0ul);
  *(uint64_t*)0x200001c0 = 0x40000000;
  *(uint32_t*)0x200001c8 = 0;
  *(uint64_t*)0x200001d0 = 0x20000040;
  *(uint64_t*)0x20000040 = 0x20000200;
  memcpy((void*)0x20000200,
         "\x02\x03\x06\x09\x10\x00\x00\x00\x00\x00\x00\x4c\x9e\x00\x00\x00\x02"
         "\x00\x13\x00\x02\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01\x05\x00"
         "\x06\x00\x20\x00\x00\x00\x0a\x00\x00\x00\x00\x00\x00\x00\x00\x05\x00"
         "\xe5\x00\x00\x07\x00\x00\x00\x1f\x00\x00\x00\x00\x00\x00\x03\x00\x00"
         "\x00\x00\x00\x00\x02\x00\x01\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00"
         "\x00\x00\x00\x05\x00\x05\x00\x00\x00\x00\x00\x0a\x00\x00\x00\x00\x00"
         "\x00\x00\xff\x17\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x17\x00\x00\x00\x00\x00\x00\x00\x00\xe5\x0b\x9a\x07\x54\x8b\x00\xb4"
         "\xa8\x34\x0d\x7d\xd4\xc2\xa7\x83\x8b\x72\x6b\xac\x59\x6a\x56\x2b\x6a"
         "\x19\x3f\x0e\x2f\x18\xae\x24\xcf\x02\x0e\x38\x06\xab\x08\xa7\x59\xe0"
         "\xe1\xba\x74\xe2\x05\x5e\x0a\x2e\xbd\xee\x3c\xf8\xcb\x33\xef\x37\xc1"
         "\x36\xa8\x92\x05\x19\x0f\x18\x46\xd6\xb0\x80\x09\x43\x44\x96\x65\xaf"
         "\x48\x30\xca\x00\x00\xd6\x5c\xd0\x95\xba\x94\x72\xaa\x06\x7e\x68\x95"
         "\x85\x99\x27\xc6\x45\x41\x80\xae\xd2\xe8\xdf\xd6\xef\xa3\x90\xd8\xb0"
         "\x63\x72\xc6\x04\xc7\xa6\xae\xe2\x57\x49\x89\xe8\x6c\xbd\x34\x91\x15"
         "\x64\x4e\x89\x24\xcc\x76\x8e\xa8\x36\x5e\x19\x1f\x77\xaf\x5f\x44\x3e"
         "\x83\x5e\x9c\x42\x37\x7f\x84\x0c\x20\x01\x59\xd6\x87\x9b\x03\xa9\x17"
         "\xdf\xd0\xc4\x13\x4c\xd8\xac\x69\xe8\x79\xa4\x56\x9a\x07\xbb\x1a\x0d"
         "\xfd\xa8\x1f\x97\xd5\x60\xb8\xae\xf6\x67\x77\x9f\x0a\x35\x67\x42\xb8"
         "\x5a\x97\xe2\xca\x28\x1b\x7f\x90\xe0\x72\x7f\x90\x9e\xfd\x82\xac\xf1"
         "\xe9\x57\x6c\xd3\x14\x17\xc9\xea\x03\xd2\xe0\xbb\x8e\x07\xe6\xa0\xf1"
         "\x6d\x62\x39\x89\xff\x7f\x00\x00\x00\x00\x00\x00\xbb\xa3\xbb\xe9\x58"
         "\x48\x3f\xc5\xf1\x87\xa2\xfb\xc8\xac\xae\xdf\xd7\x2c\xff\x2e\x9e\x50"
         "\xf2\x5a\x21\x63\x46\xd7\xec\x14\x9e\x2e\xe7\x25\x00\x00\x00\x00\x00"
         "\x00\x00\x00\x00\x00\x00\x00\x00",
         416);
  *(uint64_t*)0x20000048 = 0x80;
  *(uint64_t*)0x200001d8 = 1;
  *(uint64_t*)0x200001e0 = 0;
  *(uint64_t*)0x200001e8 = 0;
  *(uint32_t*)0x200001f0 = 0;
  syscall(__NR_sendmsg, -1, 0x200001c0ul, 0ul);
  syscall(__NR_sendmmsg, r[0], 0x20000180ul, 0x400008aul, 0ul);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0);
  for (procid = 0; procid < 6; procid++) {
    if (fork() == 0) {
      use_temporary_dir();
      do_sandbox_none();
    }
  }
  sleep(1000000);
  return 0;
}