// https://syzkaller.appspot.com/bug?id=be2e39518462291fd049f665261632ded34b79fd
// autogenerated by syzkaller (http://github.com/google/syzkaller)

#define _GNU_SOURCE
#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <signal.h>
#include <stdarg.h>
#include <stdio.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

__attribute__((noreturn)) static void doexit(int status)
{
  volatile unsigned i;
  syscall(__NR_exit_group, status);
  for (i = 0;; i++) {
  }
}
#include <errno.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>

const int kFailStatus = 67;
const int kRetryStatus = 69;

static void fail(const char* msg, ...)
{
  int e = errno;
  va_list args;
  va_start(args, msg);
  vfprintf(stderr, msg, args);
  va_end(args);
  fprintf(stderr, " (errno %d)\n", e);
  doexit((e == ENOMEM || e == EAGAIN) ? kRetryStatus : kFailStatus);
}

static void exitf(const char* msg, ...)
{
  int e = errno;
  va_list args;
  va_start(args, msg);
  vfprintf(stderr, msg, args);
  va_end(args);
  fprintf(stderr, " (errno %d)\n", e);
  doexit(kRetryStatus);
}

static uint64_t current_time_ms()
{
  struct timespec ts;

  if (clock_gettime(CLOCK_MONOTONIC, &ts))
    fail("clock_gettime failed");
  return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

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

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) {
      exitf("opendir(%s) failed due to NOFILE, exiting", dir);
    }
    exitf("opendir(%s) failed", dir);
  }
  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))
      exitf("lstat(%s) failed", filename);
    if (S_ISDIR(st.st_mode)) {
      remove_dir(filename);
      continue;
    }
    int i;
    for (i = 0;; i++) {
      if (unlink(filename) == 0)
        break;
      if (errno == EROFS) {
        break;
      }
      if (errno != EBUSY || i > 100)
        exitf("unlink(%s) failed", filename);
      if (umount2(filename, MNT_DETACH))
        exitf("umount(%s) failed", filename);
    }
  }
  closedir(dp);
  int i;
  for (i = 0;; i++) {
    if (rmdir(dir) == 0)
      break;
    if (i < 100) {
      if (errno == EROFS) {
        break;
      }
      if (errno == EBUSY) {
        if (umount2(dir, MNT_DETACH))
          exitf("umount(%s) failed", dir);
        continue;
      }
      if (errno == ENOTEMPTY) {
        if (iter < 100) {
          iter++;
          goto retry;
        }
      }
    }
    exitf("rmdir(%s) failed", dir);
  }
}

static void test();

void loop()
{
  int iter;
  for (iter = 0;; iter++) {
    char cwdbuf[256];
    sprintf(cwdbuf, "./%d", iter);
    if (mkdir(cwdbuf, 0777))
      fail("failed to mkdir");
    int pid = fork();
    if (pid < 0)
      fail("loop fork failed");
    if (pid == 0) {
      prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
      setpgrp();
      if (chdir(cwdbuf))
        fail("failed to chdir");
      test();
      doexit(0);
    }
    int status = 0;
    uint64_t start = current_time_ms();
    for (;;) {
      int res = waitpid(-1, &status, __WALL | WNOHANG);
      if (res == pid)
        break;
      usleep(1000);
      if (current_time_ms() - start > 5 * 1000) {
        kill(-pid, SIGKILL);
        kill(pid, SIGKILL);
        while (waitpid(-1, &status, __WALL) != pid) {
        }
        break;
      }
    }
    remove_dir(cwdbuf);
  }
}

long r[1];
void test()
{
  memset(r, -1, sizeof(r));
  syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0);
  memcpy((void*)0x20029ff6, "./file0", 8);
  syscall(__NR_mkdir, 0x20029ff6, 0);
  memcpy((void*)0x2000a000, "./file0", 8);
  memcpy((void*)0x20014ff8, "./file0", 8);
  memcpy((void*)0x20014000, "proc", 5);
  syscall(__NR_mount, 0x2000a000, 0x20014ff8, 0x20014000, 0, 0x20fc9000);
  r[0] = syscall(__NR_socket, 0x10, 3, 6);
  *(uint64_t*)0x2000b000 = 0x2000f000;
  *(uint32_t*)0x2000b008 = 0xc;
  *(uint64_t*)0x2000b010 = 0x20008000;
  *(uint64_t*)0x2000b018 = 1;
  *(uint64_t*)0x2000b020 = 0;
  *(uint64_t*)0x2000b028 = 0;
  *(uint32_t*)0x2000b030 = 0;
  *(uint16_t*)0x2000f000 = 0x10;
  *(uint16_t*)0x2000f002 = 0;
  *(uint32_t*)0x2000f004 = 0;
  *(uint32_t*)0x2000f008 = 0;
  *(uint64_t*)0x20008000 = 0x20417ec8;
  *(uint64_t*)0x20008008 = 0x138;
  *(uint32_t*)0x20417ec8 = 0x138;
  *(uint16_t*)0x20417ecc = 0x10;
  *(uint16_t*)0x20417ece = 0x713;
  *(uint32_t*)0x20417ed0 = 0;
  *(uint32_t*)0x20417ed4 = 0;
  *(uint32_t*)0x20417ed8 = htobe32(0);
  *(uint32_t*)0x20417ee8 = htobe32(0xe0000002);
  *(uint16_t*)0x20417ef8 = 0;
  *(uint16_t*)0x20417efa = htobe16(0);
  *(uint16_t*)0x20417efc = 0;
  *(uint16_t*)0x20417efe = htobe16(0);
  *(uint16_t*)0x20417f00 = 0;
  *(uint8_t*)0x20417f02 = 0;
  *(uint8_t*)0x20417f03 = 0;
  *(uint8_t*)0x20417f04 = 0;
  *(uint32_t*)0x20417f08 = 0;
  *(uint32_t*)0x20417f0c = 0;
  *(uint32_t*)0x20417f10 = htobe32(0x7f000001);
  *(uint32_t*)0x20417f20 = 0;
  *(uint8_t*)0x20417f24 = 0x6c;
  *(uint32_t*)0x20417f28 = htobe32(0xe0000001);
  *(uint64_t*)0x20417f38 = 0;
  *(uint64_t*)0x20417f40 = 0;
  *(uint64_t*)0x20417f48 = 0;
  *(uint64_t*)0x20417f50 = 0;
  *(uint64_t*)0x20417f58 = 0;
  *(uint64_t*)0x20417f60 = 0;
  *(uint64_t*)0x20417f68 = 0;
  *(uint64_t*)0x20417f70 = 0;
  *(uint64_t*)0x20417f78 = 0;
  *(uint64_t*)0x20417f80 = 0;
  *(uint64_t*)0x20417f88 = 0;
  *(uint64_t*)0x20417f90 = 0;
  *(uint32_t*)0x20417f98 = 0;
  *(uint32_t*)0x20417f9c = 0;
  *(uint32_t*)0x20417fa0 = 0;
  *(uint32_t*)0x20417fa4 = 0;
  *(uint32_t*)0x20417fa8 = 0;
  *(uint16_t*)0x20417fac = 0xa;
  *(uint8_t*)0x20417fae = 1;
  *(uint8_t*)0x20417faf = 0;
  *(uint8_t*)0x20417fb0 = 0;
  *(uint16_t*)0x20417fb8 = 0x48;
  *(uint16_t*)0x20417fba = 3;
  memcpy((void*)0x20417fbc,
         "\x64\x65\x66\x6c\x61\x74\x65\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"
         "\x00\x00\x00\x00\x00\x00\x00\xf1\xff\xff\xff\x00\x00\x00\x00\x00\x00"
         "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00",
         64);
  *(uint32_t*)0x20417ffc = 0;
  syscall(__NR_sendmsg, r[0], 0x2000b000, 0);
}

int main()
{
  char* cwd = get_current_dir_name();
  for (;;) {
    if (chdir(cwd))
      fail("failed to chdir");
    use_temporary_dir();
    loop();
  }
}