// https://syzkaller.appspot.com/bug?id=de6519e18a472f06a6b530c84c3be8a29c554900
// autogenerated by syzkaller (http://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <linux/futex.h>
#include <pthread.h>
#include <sched.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/wait.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 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 loop();

static void sandbox_common()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  setpgrp();
  setsid();

  struct rlimit rlim;
  rlim.rlim_cur = rlim.rlim_max = 128 << 20;
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 8 << 20;
  setrlimit(RLIMIT_MEMLOCK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 1 << 20;
  setrlimit(RLIMIT_FSIZE, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 1 << 20;
  setrlimit(RLIMIT_STACK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 0;
  setrlimit(RLIMIT_CORE, &rlim);

#define CLONE_NEWCGROUP 0x02000000

  unshare(CLONE_NEWNS);
  unshare(CLONE_NEWIPC);
  unshare(CLONE_NEWCGROUP);
  unshare(CLONE_NEWNET);
  unshare(CLONE_NEWUTS);
  unshare(CLONE_SYSVSEM);
}

static int do_sandbox_none(int executor_pid, bool enable_tun)
{
  unshare(CLONE_NEWPID);
  int pid = fork();
  if (pid < 0)
    fail("sandbox fork failed");
  if (pid)
    return pid;

  sandbox_common();

  loop();
  doexit(1);
}

static void test();

void loop()
{
  while (1) {
    test();
  }
}

struct thread_t {
  int created, running, call;
  pthread_t th;
};

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

static void* thr(void* arg)
{
  struct thread_t* th = (struct thread_t*)arg;
  for (;;) {
    while (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE))
      syscall(SYS_futex, &th->running, FUTEX_WAIT, 0, 0);
    execute_call(th->call);
    __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
    __atomic_store_n(&th->running, 0, __ATOMIC_RELEASE);
    syscall(SYS_futex, &th->running, FUTEX_WAKE);
  }
  return 0;
}

static void execute(int num_calls)
{
  int call, thread;
  running = 0;
  for (call = 0; call < num_calls; call++) {
    for (thread = 0; thread < sizeof(threads) / sizeof(threads[0]);
         thread++) {
      struct thread_t* th = &threads[thread];
      if (!th->created) {
        th->created = 1;
        pthread_attr_t attr;
        pthread_attr_init(&attr);
        pthread_attr_setstacksize(&attr, 128 << 10);
        pthread_create(&th->th, &attr, thr, th);
      }
      if (!__atomic_load_n(&th->running, __ATOMIC_ACQUIRE)) {
        th->call = call;
        __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
        __atomic_store_n(&th->running, 1, __ATOMIC_RELEASE);
        syscall(SYS_futex, &th->running, FUTEX_WAKE);
        if (collide && call % 2)
          break;
        struct timespec ts;
        ts.tv_sec = 0;
        ts.tv_nsec = 20 * 1000 * 1000;
        syscall(SYS_futex, &th->running, FUTEX_WAIT, 1, &ts);
        if (running)
          usleep((call == num_calls - 1) ? 10000 : 1000);
        break;
      }
    }
  }
}

#ifndef __NR_bpf
#define __NR_bpf 321
#endif

long r[4];
uint64_t procid;
void execute_call(int call)
{
  switch (call) {
  case 0:
    syscall(__NR_mmap, 0x20000000, 0xfff000, 0x3, 0x32, 0xffffffff,
            0x0);
    break;
  case 1:
    if (syscall(__NR_socketpair, 0x1, 0x2, 0x0, 0x20800ff8) != -1) {
      r[0] = *(uint32_t*)0x20800ff8;
      r[1] = *(uint32_t*)0x20800ffc;
    }
    break;
  case 2:
    *(uint32_t*)0x20b4cfd0 = 0x1;
    *(uint32_t*)0x20b4cfd4 = 0x2;
    *(uint64_t*)0x20b4cfd8 = 0x20ef3000;
    *(uint64_t*)0x20b4cfe0 = 0x20b4d000;
    *(uint32_t*)0x20b4cfe8 = 0x1;
    *(uint32_t*)0x20b4cfec = 0x80;
    *(uint64_t*)0x20b4cff0 = 0x2000a000;
    *(uint32_t*)0x20b4cff8 = 0x0;
    *(uint32_t*)0x20b4cffc = 0x0;
    *(uint8_t*)0x20ef3000 = 0xb7;
    *(uint8_t*)0x20ef3001 = 0x0;
    *(uint16_t*)0x20ef3002 = 0x0;
    *(uint32_t*)0x20ef3004 = 0x0;
    *(uint8_t*)0x20ef3008 = 0x95;
    *(uint8_t*)0x20ef3009 = 0x0;
    *(uint16_t*)0x20ef300a = 0x0;
    *(uint32_t*)0x20ef300c = 0x0;
    memcpy((void*)0x20b4d000, "syseO", 6);
    r[2] = syscall(__NR_bpf, 0x5, 0x20b4cfd0, 0x30);
    break;
  case 3:
    r[3] = syscall(__NR_socket, 0x29, 0x5, 0x0);
    break;
  case 4:
    *(uint64_t*)0x20d33000 = 0x209e7000;
    *(uint64_t*)0x20d33008 = 0x1;
    memcpy((void*)0x209e7000, "\xfd", 1);
    syscall(__NR_writev, r[1], 0x20d33000, 0x1);
    break;
  case 5:
    *(uint32_t*)0x20ff9ff8 = r[0];
    *(uint32_t*)0x20ff9ffc = r[2];
    syscall(__NR_ioctl, r[3], 0x89e0, 0x20ff9ff8);
    break;
  }
}

void test()
{
  memset(r, -1, sizeof(r));
  execute(6);
  collide = 1;
  execute(6);
}

int main()
{
  int i;
  for (i = 0; i < 8; i++) {
    if (fork() == 0) {
      procid = i;
      use_temporary_dir();
      int pid = do_sandbox_none(i, false);
      int status = 0;
      while (waitpid(pid, &status, __WALL) != pid) {
      }
      return 0;
    }
  }
  sleep(1000000);
  return 0;
}