// https://syzkaller.appspot.com/bug?id=f82f8fba49a7138ffc83001e6ca9a19d6d9c4955
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

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

static unsigned long long procid;

static __thread int skip_segv;
static __thread jmp_buf segv_env;

static void segv_handler(int sig, siginfo_t* info, void* ctx)
{
  uintptr_t addr = (uintptr_t)info->si_addr;
  const uintptr_t prog_start = 1 << 20;
  const uintptr_t prog_end = 100 << 20;
  if (__atomic_load_n(&skip_segv, __ATOMIC_RELAXED) &&
      (addr < prog_start || addr > prog_end)) {
    _longjmp(segv_env, 1);
  }
  exit(sig);
}

static void install_segv_handler(void)
{
  struct sigaction sa;
  memset(&sa, 0, sizeof(sa));
  sa.sa_sigaction = segv_handler;
  sa.sa_flags = SA_NODEFER | SA_SIGINFO;
  sigaction(SIGSEGV, &sa, NULL);
  sigaction(SIGBUS, &sa, NULL);
}

#define NONFAILING(...)                                                        \
  {                                                                            \
    __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    if (_setjmp(segv_env) == 0) {                                              \
      __VA_ARGS__;                                                             \
    }                                                                          \
    __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
  }

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 remove_dir(const char* dir)
{
  DIR* dp;
  struct dirent* ep;
  dp = opendir(dir);
  if (dp == NULL)
    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;
    }
    if (unlink(filename))
      exit(1);
  }
  closedir(dp);
  if (rmdir(dir))
    exit(1);
}

static void execute_one(void);

#define WAIT_FLAGS 0

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);
      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 < 5 * 1000)
        continue;
      kill_and_wait(pid, &status);
      break;
    }
    remove_dir(cwdbuf);
  }
}

#ifndef SYS_mmap
#define SYS_mmap 197
#endif
#ifndef SYS_open
#define SYS_open 5
#endif
#ifndef SYS_write
#define SYS_write 4
#endif
#ifndef SYS_writev
#define SYS_writev 121
#endif

uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff};

void execute_one(void)
{
  intptr_t res = 0;
  NONFAILING(memcpy((void*)0x200001c0, "./file0\000", 8));
  res = syscall(SYS_open, 0x200001c0ul, 0x2088611ul, 0ul);
  if (res != -1)
    r[0] = res;
  NONFAILING(memcpy((void*)0x20000000, "./file0\000", 8));
  res = syscall(SYS_open, 0x20000000ul, 0x2088611ul, 0ul);
  if (res != -1)
    r[1] = res;
  NONFAILING(*(uint64_t*)0x20000340 = 0x20000000);
  NONFAILING(*(uint64_t*)0x20000348 = 0x2cfea);
  syscall(SYS_writev, r[1], 0x20000340ul, 0x1000000000000013ul);
  NONFAILING(memcpy((void*)0x200000c0,
                    "\xd8\xf5\x9f\x9b\x3f\xad\x61\x92\xdd\xd9\x5c\x9a\x7d\x0f"
                    "\x12\x2f\xf5\x67\x38\xe4\x5b\x90\x05\x18\x8c\xe1\x58\x3e"
                    "\x8d\x30\x2f\x80\x87\x0b\x6d\x36\x84\x4b\xdf",
                    39));
  syscall(SYS_write, r[1], 0x200000c0ul, 0x27ul);
  syscall(SYS_writev, r[0], 0x20000340ul, 0x10000000000000d8ul);
  NONFAILING(memcpy((void*)0x20000000, "./file0\000", 8));
  syscall(SYS_open, 0x20000000ul, 0ul, 0ul);
}
int main(void)
{
  syscall(SYS_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x1012ul, -1, 0ul, 0ul);
  install_segv_handler();
  for (procid = 0; procid < 6; procid++) {
    if (fork() == 0) {
      use_temporary_dir();
      loop();
    }
  }
  sleep(1000000);
  return 0;
}