// https://syzkaller.appspot.com/bug?id=084c44fc65f5f3bcef2617c9209ece9d8c6416eb
// 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 <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>

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_dev(volatile long a0, volatile long a1, volatile long a2)
{
  if (a0 == 0xc || a0 == 0xb) {
    char buf[128];
    sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1,
            (uint8_t)a2);
    return open(buf, O_RDWR, 0);
  } else {
    unsigned long nb = a1;
    char buf[1024];
    char* hash;
    strncpy(buf, (char*)a0, sizeof(buf) - 1);
    buf[sizeof(buf) - 1] = 0;
    while ((hash = strchr(buf, '#'))) {
      *hash = '0' + (char)(nb % 10);
      nb /= 10;
    }
    return open(buf, a2, 0);
  }
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir)
{
  int iter = 0;
  DIR* dp = 0;
  const int umount_flags = MNT_FORCE | UMOUNT_NOFOLLOW;

retry:
  while (umount2(dir, umount_flags) == 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, umount_flags) == 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, umount_flags))
        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, umount_flags))
          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 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)
{
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  int i, call, thread;
  for (call = 0; call < 10; 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);
      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);
    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 (;;) {
      sleep_ms(10);
      if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
        break;
      if (current_time_ms() - start < 5000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
    remove_dir(cwdbuf);
  }
}

uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff};

void execute_call(int call)
{
  intptr_t res = 0;
  switch (call) {
  case 0:
    //  prctl$PR_SCHED_CORE arguments: [
    //    option: const = 0x3e (8 bytes)
    //    cmd: intptr = 0x1 (8 bytes)
    //    pid: pid (resource)
    //    type: pid_type = 0x2 (8 bytes)
    //    uaddr: nil
    //  ]
    syscall(__NR_prctl, /*option=*/0x3eul, /*cmd=*/1ul, /*pid=*/0,
            /*type=PIDTYPE_PGID*/ 2ul, /*uaddr=*/0ul);
    break;
  case 1:
    //  prlimit64 arguments: [
    //    pid: pid (resource)
    //    res: rlimit_type = 0xe (8 bytes)
    //    new: nil
    //    old: nil
    //  ]
    syscall(__NR_prlimit64, /*pid=*/0, /*res=RLIMIT_RTPRIO*/ 0xeul, /*new=*/0ul,
            /*old=*/0ul);
    break;
  case 2:
    //  openat$sequencer arguments: [
    //    fd: const = 0xffffffffffffff9c (8 bytes)
    //    file: ptr[in, buffer] {
    //      buffer: {2f 64 65 76 2f 73 65 71 75 65 6e 63 65 72 00} (length 0xf)
    //    }
    //    flags: open_flags = 0x0 (4 bytes)
    //    mode: const = 0x0 (2 bytes)
    //  ]
    //  returns fd_seq
    memcpy((void*)0x200000000300, "/dev/sequencer\000", 15);
    syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x200000000300ul,
            /*flags=*/0, /*mode=*/0);
    break;
  case 3:
    //  syz_open_dev$sndmidi arguments: [
    //    dev: ptr[in, buffer] {
    //      buffer: {2f 64 65 76 2f 73 6e 64 2f 6d 69 64 69 43 23 44 23 00}
    //      (length 0x12)
    //    }
    //    id: intptr = 0x2 (8 bytes)
    //    flags: open_flags = 0x141102 (8 bytes)
    //  ]
    //  returns fd_midi
    memcpy((void*)0x2000000004c0, "/dev/snd/midiC#D#\000", 18);
    res = -1;
    res = syz_open_dev(/*dev=*/0x2000000004c0, /*id=*/2,
                       /*flags=O_SYNC|O_NOCTTY|O_NOATIME|O_RDWR*/ 0x141102);
    if (res != -1)
      r[0] = res;
    break;
  case 4:
    //  writev arguments: [
    //    fd: fd (resource)
    //    vec: ptr[in, array[iovec[in, array[int8]]]] {
    //      array[iovec[in, array[int8]]] {
    //        iovec[in, array[int8]] {
    //          addr: ptr[in, buffer] {
    //            buffer: {94} (length 0x1)
    //          }
    //          len: len = 0xf000 (8 bytes)
    //        }
    //        iovec[in, array[int8]] {
    //          addr: nil
    //          len: len = 0x0 (8 bytes)
    //        }
    //      }
    //    }
    //    vlen: len = 0x2 (8 bytes)
    //  ]
    *(uint64_t*)0x200000000840 = 0x2000000002c0;
    memset((void*)0x2000000002c0, 148, 1);
    *(uint64_t*)0x200000000848 = 0xf000;
    *(uint64_t*)0x200000000850 = 0;
    *(uint64_t*)0x200000000858 = 0;
    syscall(__NR_writev, /*fd=*/r[0], /*vec=*/0x200000000840ul, /*vlen=*/2ul);
    break;
  case 5:
    //  openat$ptmx arguments: [
    //    fd: const = 0xffffffffffffff9c (8 bytes)
    //    file: ptr[in, buffer] {
    //      buffer: {2f 64 65 76 2f 70 74 6d 78 00} (length 0xa)
    //    }
    //    flags: open_flags = 0x0 (4 bytes)
    //    mode: const = 0x0 (2 bytes)
    //  ]
    //  returns fd_tty
    memcpy((void*)0x200000000300, "/dev/ptmx\000", 10);
    res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul,
                  /*file=*/0x200000000300ul, /*flags=*/0, /*mode=*/0);
    if (res != -1)
      r[1] = res;
    break;
  case 6:
    //  ioctl$TIOCSETD arguments: [
    //    fd: fd_tty (resource)
    //    cmd: const = 0x5423 (4 bytes)
    //    arg: ptr[in, int32] {
    //      int32 = 0xf (4 bytes)
    //    }
    //  ]
    *(uint32_t*)0x2000000000c0 = 0xf;
    syscall(__NR_ioctl, /*fd=*/r[1], /*cmd=*/0x5423, /*arg=*/0x2000000000c0ul);
    break;
  case 7:
    //  fcntl$dupfd arguments: [
    //    fd: fd (resource)
    //    cmd: fcntl_dupfd = 0x0 (8 bytes)
    //    arg: fd (resource)
    //  ]
    //  returns fd
    res = syscall(__NR_fcntl, /*fd=*/r[1], /*cmd=*/0ul, /*arg=*/r[1]);
    if (res != -1)
      r[2] = res;
    break;
  case 8:
    //  ioctl$TCFLSH arguments: [
    //    fd: fd_tty (resource)
    //    cmd: const = 0x400455c8 (4 bytes)
    //    arg: intptr = 0x2 (8 bytes)
    //  ]
    syscall(__NR_ioctl, /*fd=*/r[2], /*cmd=*/0x400455c8, /*arg=*/2ul);
    break;
  case 9:
    //  ioctl$TIOCSTI arguments: [
    //    fd: fd_tty (resource)
    //    cmd: const = 0x5412 (4 bytes)
    //    arg: ptr[in, int8] {
    //      int8 = 0xfc (1 bytes)
    //    }
    //  ]
    *(uint8_t*)0x200000000040 = 0xfc;
    syscall(__NR_ioctl, /*fd=*/r[2], /*cmd=*/0x5412, /*arg=*/0x200000000040ul);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  for (procid = 0; procid < 4; procid++) {
    if (fork() == 0) {
      use_temporary_dir();
      loop();
    }
  }
  sleep(1000000);
  return 0;
}