// https://syzkaller.appspot.com/bug?id=8d8ed75a599095367fee3d51bb8794980a35adae
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.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/mount.h>
#include <sys/prctl.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/futex.h>
#include <linux/loop.h>

#ifndef __NR_memfd_create
#define __NR_memfd_create 319
#endif

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 void thread_start(void* (*fn)(void*), void* arg)
{
  pthread_t th;
  pthread_attr_t attr;
  pthread_attr_init(&attr);
  pthread_attr_setstacksize(&attr, 128 << 10);
  int i = 0;
  for (; i < 100; i++) {
    if (pthread_create(&th, &attr, fn, arg) == 0) {
      pthread_attr_destroy(&attr);
      return;
    }
    if (errno == EAGAIN) {
      usleep(50);
      continue;
    }
    break;
  }
  exit(1);
}

typedef struct {
  int state;
} event_t;

static void event_init(event_t* ev)
{
  ev->state = 0;
}

static void event_reset(event_t* ev)
{
  ev->state = 0;
}

static void event_set(event_t* ev)
{
  if (ev->state)
    exit(1);
  __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE);
  syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG, 1000000);
}

static void event_wait(event_t* ev)
{
  while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
    syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0);
}

static int event_isset(event_t* ev)
{
  return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE);
}

static int event_timedwait(event_t* ev, uint64_t timeout)
{
  uint64_t start = current_time_ms();
  uint64_t now = start;
  for (;;) {
    uint64_t remain = timeout - (now - start);
    struct timespec ts;
    ts.tv_sec = remain / 1000;
    ts.tv_nsec = (remain % 1000) * 1000 * 1000;
    syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts);
    if (__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
      return 1;
    now = current_time_ms();
    if (now - start > timeout)
      return 0;
  }
}

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;
}

static long syz_open_procfs(volatile long a0, volatile long a1)
{
  char buf[128];
  memset(buf, 0, sizeof(buf));
  if (a0 == 0) {
    snprintf(buf, sizeof(buf), "/proc/self/%s", (char*)a1);
  } else if (a0 == -1) {
    snprintf(buf, sizeof(buf), "/proc/thread-self/%s", (char*)a1);
  } else {
    snprintf(buf, sizeof(buf), "/proc/self/task/%d/%s", (int)a0, (char*)a1);
  }
  int fd = open(buf, O_RDWR);
  if (fd == -1)
    fd = open(buf, O_RDONLY);
  return fd;
}

struct fs_image_segment {
  void* data;
  uintptr_t size;
  uintptr_t offset;
};
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;
  int memfd = syscall(__NR_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, volatile long change_dir)
{
  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;
    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);
    close(memfd);
  }
  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 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")) {
  }
}

struct thread_t {
  int created, call;
  event_t ready, done;
};

static struct thread_t threads[16];
static void execute_call(int call);
static int running;

static void* thr(void* arg)
{
  struct thread_t* th = (struct thread_t*)arg;
  for (;;) {
    event_wait(&th->ready);
    event_reset(&th->ready);
    execute_call(th->call);
    __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
    event_set(&th->done);
  }
  return 0;
}

static void execute_one(void)
{
  int i, call, thread;
  for (call = 0; call < 3; call++) {
    for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0]));
         thread++) {
      struct thread_t* th = &threads[thread];
      if (!th->created) {
        th->created = 1;
        event_init(&th->ready);
        event_init(&th->done);
        event_set(&th->done);
        thread_start(thr, th);
      }
      if (!event_isset(&th->done))
        continue;
      event_reset(&th->done);
      th->call = call;
      __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
      event_set(&th->ready);
      event_timedwait(&th->done, 50 + (call == 0 ? 50 : 0));
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
}

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_call(int call)
{
  intptr_t res = 0;
  switch (call) {
  case 0:
    memcpy((void*)0x20000000, "reiserfs\000", 9);
    memcpy((void*)0x20000100, "./file0\000", 8);
    *(uint64_t*)0x20000540 = 0x20000140;
    memcpy((void*)0x20000140, "\x8c\xb6\x37", 3);
    *(uint64_t*)0x20000548 = 3;
    *(uint64_t*)0x20000550 = 1;
    *(uint64_t*)0x20000558 = 0x20000600;
    memcpy((void*)0x20000600, "\x00\x84\x09", 3);
    *(uint64_t*)0x20000560 = 3;
    *(uint64_t*)0x20000568 = 4;
    *(uint64_t*)0x20000570 = 0x200003c0;
    memcpy((void*)0x200003c0,
           "\xcf\x58\xf9\xb6\xb0\x97\x28\x72\x18\xce\x56\xf2\x50\xb4\x26\xfd"
           "\x15\x34\xa8\x24\x13\x97\xcf\xab\x6d\x88\x16\xfa\x4b\xb4\x5c\x3f"
           "\x9f\xdd\xf8\x76\xb2\x69\xc1\xe8\x59\xce\xbe\x21\xb7\xd9\x24\x4b"
           "\x1f\xd8\xf4\x11\xc2\xe7\x5b\x40\x44\x0e\x6e\x93\x65\x6e\xcb\xb4"
           "\x9b\xee\xac\x1c\x75\x71\x47\x8c\xa3\xc9\x9e\xc9\x07\x4a\xeb\xad"
           "\xf4\x46\x2d\x55\x73\x8c\xec\xdf\x1a\xe2\x86\x2f\x84\x19\x26\xf1"
           "\x5b\x27\x70\x6d\xc5\xf5\x8b\x7a\x97\xed\xdb\x38\x5d\x14\xcb\x9c"
           "\x8a\xc2\x40\x14\x98\x49\x6f\xac\x00\x4e\x57\x41\x17\x8f\x6b\x0d"
           "\x2f\xd5\x0e\x23\x2c\xd6\xf6\x69\x95\x25\x9a\x8c\x57\x3a\x6b\xc6"
           "\xad\x4f\x95\x0f\xf4\x07\xdf\x67\xc0\xd0\x0e\xfb\xe7\xbf\x66\xea"
           "\xce\xf1\x43\x9b\x60\xe4\xdb\xf2\x4b\x6e\xed\x04\x20\x2c\x85\x42"
           "\xf1\x1f\x3f\x66\x65\x80\x5e\xac\x43\xe3\x13\xd1\x3f\xaf\x64\x88"
           "\xa3\x74\xe9\x55\xb4\xe0\xd4\x6b\x82\xb2\x44\x01\xac",
           205);
    *(uint64_t*)0x20000578 = 0xcd;
    *(uint64_t*)0x20000580 = 7;
    *(uint64_t*)0x20000588 = 0x20010000;
    memcpy((void*)0x20010000,
           "\x00\x04\x00\x00\xec\x01\x00\x00\x13\x02\x00\x00\x12\x00\x00\x00"
           "\x00\x00\x00\x00\x00\x02\x00\x00\x00\x01\x00\x00\x61\x1c\xad\x49"
           "\xe1\x00\x00\x00\x1e\x00\x00\x00\x00\x00\x00\x00\x00\x10\xcc\x03"
           "\x10\x00\x01\x00\x52\x65\x49\x73\x45\x72\x33\x46\x73\x00\x00\x00"
           "\x02\x00\x00\x00\x02\x00\x01\x00\x02\x00\x01\x02\x00\x00\x00\x00"
           "\x01\x00\x00\x00\x12\x31\x2a\x23\x12\x12\x33\x12\x33\x12\x31\x12"
           "\x34\x13\x41\x24\x12\x73\x79\x7a\x6b\x61\x6c\x6c\x65\x72\x00\x00"
           "\x00\x00\x00\x00\x00\x01\x00\x1e\x00\x3a\xc1\x65\x5f\x00\x4e\xed",
           128);
    *(uint64_t*)0x20000590 = 0x80;
    *(uint64_t*)0x20000598 = 0x10000;
    *(uint64_t*)0x200005a0 = 0x20000040;
    memcpy((void*)0x20000040,
           "\x00\x00\x00\x00\x00\x00\x05\x00\x08\x00\x00\x00\x01\x10\x00\x00"
           "\x03\x10\x00\x48\xb2\x56\x07\x81\x8b\x96\xe2\x7e\xa5\x80\x19\x56"
           "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x9e\x08",
           45);
    *(uint64_t*)0x200005a8 = 0x2d;
    *(uint64_t*)0x200005b0 = 0x100c0;
    *(uint64_t*)0x200005b8 = 0x20001a00;
    memcpy(
        (void*)0x20001a00,
        "\x00\x04\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x12\x00\x00\x00\x00"
        "\x00\x00\x00\x00\x02\x00\x00\x00\x01\x00\x00\x61\x1c\xad\x49\xe1\x00"
        "\x00\x00\x1e\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
        "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xf4\x50\x98\x12"
        "\x2a\x16\x2b\x00\x17\x31\xda\x04\x98\x0e\x00\x00\x66\xd9\xca\x9b\x08"
        "\x8f\x7a\xfe\xe7\x42\xa2\xaa\xc9\x3d\x10\x58\x68\xc7\x2e\xdb\x81\x4c"
        "\xc6\x6a\x9a\x15\x09\xf9\x0b\xd4\x13\xa2\xb6\x2d\xa4\x39\x9d\xeb\xc7"
        "\xfe\xcf\x87\xab\xdb\x53\x1e\x95\xf9\x2a\x62\xd9\x60\xae\x64\xfe\x76"
        "\x34\x4e\x25\x43\xf4\xe6\xfb\x0d\x51\x55\x05\x35\xcc\x7a\x26\x0a\x24"
        "\xc2\xf4\xef\xbd\xe4\x5c\x75\x51\x53\x41\x8c\xe7\xf3\x7b\x89\xcf\xa2"
        "\xdb\x01\x7f\xa7\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
        185);
    *(uint64_t*)0x200005c0 = 0xb9;
    *(uint64_t*)0x200005c8 = 0x212000;
    *(uint64_t*)0x200005d0 = 0x20011300;
    memcpy((void*)0x20011300,
           "\x01\x00\x02\x00\x5c\x0f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
           "\x00\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00"
           "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x2c\x00\xd4\x0f\x01\x00"
           "\x01\x00\x00\x00\x02\x00\x00\x00\x01\x00\x00\x00\xf4\x01\x00\x00"
           "\x02\x00\x30\x00\xa4\x0f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
           "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
           96);
    *(uint64_t*)0x200005d8 = 0x60;
    *(uint64_t*)0x200005e0 = 0x213000;
    *(uint64_t*)0x200005e8 = 0x20000280;
    memcpy(
        (void*)0x20000280,
        "\x00\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x02\x00\x00\x00\x28"
        "\x00\x04\x00\x02\x00\x00\x00\x00\x00\x00\x00\x01\x00\x00\x00\x20\x00"
        "\x04\x00\x2e\x2e\x00\x00\x00\x00\x00\x00\x2e\x00\xe2\xff\x00\x00\x00"
        "\x00\xed\x41\x00\x00\x03\x00\x00\x3a\xc1\x65\x5f\x3a\xc1\x65\x5f\x3a"
        "\xc1\x65\xea\x00\x00\x00\x00\x00\x00\x00\x00\x00\xf3\xff",
        82);
    *(uint64_t*)0x200005f0 = 0x52;
    *(uint64_t*)0x200005f8 = 0x213fa0;
    *(uint64_t*)0x20000180 = 0;
    syz_mount_image(0x20000000, 0x20000100, 0x400010, 8, 0x20000540, 0x20040a,
                    0x20000180, 0);
    break;
  case 1:
    memcpy((void*)0x20000300, "fd/4\000", 5);
    res = -1;
    res = syz_open_procfs(0, 0x20000300);
    if (res != -1)
      r[0] = res;
    break;
  case 2:
    *(uint32_t*)0x20000140 = 0x30;
    *(uint32_t*)0x20000144 = 5;
    *(uint64_t*)0x20000148 = 0;
    *(uint64_t*)0x20000150 = 0;
    *(uint64_t*)0x20000158 = 0;
    *(uint64_t*)0x20000160 = 0;
    *(uint32_t*)0x20000168 = 0;
    *(uint32_t*)0x2000016c = 0;
    syscall(__NR_write, r[0], 0x20000140ul, 0xfffffda2ul);
    break;
  }
}
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);
  use_temporary_dir();
  loop();
  return 0;
}