// https://syzkaller.appspot.com/bug?id=0a60b828818a364deb4721d58b2ed5167b1f6296
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <sys/types.h>

#include <dirent.h>
#include <errno.h>
#include <pwd.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/endian.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

static void kill_and_wait(int pid, int* status)
{
  kill(pid, SIGKILL);
  while (waitpid(-1, status, 0) != pid) {
  }
}

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 reset_flags(const char* filename)
{
  struct stat st;
  if (lstat(filename, &st))
    exit(1);
  st.st_flags &= ~(SF_NOUNLINK | UF_NOUNLINK | SF_IMMUTABLE | UF_IMMUTABLE |
                   SF_APPEND | UF_APPEND);
  if (lchflags(filename, st.st_flags))
    exit(1);
}
static void __attribute__((noinline)) remove_dir(const char* dir)
{
  DIR* dp = opendir(dir);
  if (dp == NULL) {
    if (errno == EACCES) {
      if (rmdir(dir))
        exit(1);
      return;
    }
    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);
    struct stat st;
    if (lstat(filename, &st))
      exit(1);
    if (S_ISDIR(st.st_mode)) {
      remove_dir(filename);
      continue;
    }
    if (unlink(filename)) {
      if (errno == EPERM) {
        reset_flags(filename);
        reset_flags(dir);
        if (unlink(filename) == 0)
          continue;
      }
      exit(1);
    }
  }
  closedir(dp);
  while (rmdir(dir)) {
    if (errno == EPERM) {
      reset_flags(dir);
      if (rmdir(dir) == 0)
        break;
    }
    exit(1);
  }
}

static void execute_one(void);

#define WAIT_FLAGS 0

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);
      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[2] = {0xffffffffffffffff, 0xffffffffffffffff};

void execute_one(void)
{
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  memcpy((void*)0x200000001040, "./file0\000", 8);
  syscall(SYS_mkdir, /*path=*/0x200000001040ul, /*mode=S_IXOTH*/ 1ul);
  memcpy((void*)0x200000000080, ".\000", 2);
  res = syscall(SYS_open, /*file=*/0x200000000080ul,
                /*flags=O_EMPTY_PATH*/ 0x2000000ul, /*mode=*/0ul);
  if (res != -1)
    r[0] = res;
  memcpy((void*)0x200000000080, ".\000", 2);
  res =
      syscall(SYS_open, /*file=*/0x200000000080ul, /*flags=*/0ul, /*mode=*/0ul);
  if (res != -1)
    r[1] = res;
  memcpy((void*)0x2000000001c0, "./file1\000", 8);
  syscall(SYS_mkdirat, /*fd=*/r[1], /*path=*/0x2000000001c0ul, /*mode=*/0ul);
  memcpy((void*)0x200000000380,
         "./"
         "file0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\000",
         250);
  syscall(SYS_mkdir, /*path=*/0x200000000380ul, /*mode=*/0ul);
  memcpy((void*)0x200000000240,
         "./"
         "file0aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
         "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa\000",
         250);
  memcpy((void*)0x200000000140, "./file0/file0\000", 14);
  syscall(SYS_renameat, /*oldfd=*/r[1], /*old=*/0x200000000240ul,
          /*newfd=*/r[1], /*new=*/0x200000000140ul);
  memcpy((void*)0x200000000340, "./file0/file0\000", 14);
  memcpy((void*)0x200000000380, "./file1\000", 8);
  syscall(SYS_renameat, /*oldfd=*/r[0], /*old=*/0x200000000340ul,
          /*newfd=*/r[1], /*new=*/0x200000000380ul);
}
int main(void)
{
  syscall(SYS_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x1012ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  use_temporary_dir();
  loop();
  return 0;
}