// https://syzkaller.appspot.com/bug?id=56c63f6ab53577234693cac81b10384cfbf30d3e
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <sched.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#include <linux/capability.h>
#include <linux/futex.h>

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 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);
}

#define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off))
#define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len)               \
  *(type*)(addr) =                                                             \
      htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) |           \
            (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len))))

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 void setup_common()
{
  if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
  }
}

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 = (200 << 20);
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 32 << 20;
  setrlimit(RLIMIT_MEMLOCK, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 136 << 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);
  rlim.rlim_cur = rlim.rlim_max = 256;
  setrlimit(RLIMIT_NOFILE, &rlim);
  if (unshare(CLONE_NEWNS)) {
  }
  if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
  }
  if (unshare(CLONE_NEWIPC)) {
  }
  if (unshare(0x02000000)) {
  }
  if (unshare(CLONE_NEWUTS)) {
  }
  if (unshare(CLONE_SYSVSEM)) {
  }
  typedef struct {
    const char* name;
    const char* value;
  } sysctl_t;
  static const sysctl_t sysctls[] = {
      {"/proc/sys/kernel/shmmax", "16777216"},
      {"/proc/sys/kernel/shmall", "536870912"},
      {"/proc/sys/kernel/shmmni", "1024"},
      {"/proc/sys/kernel/msgmax", "8192"},
      {"/proc/sys/kernel/msgmni", "1024"},
      {"/proc/sys/kernel/msgmnb", "1024"},
      {"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
  };
  unsigned i;
  for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
    write_file(sysctls[i].name, sysctls[i].value);
}

static int wait_for_loop(int pid)
{
  if (pid < 0)
    exit(1);
  int status = 0;
  while (waitpid(-1, &status, __WALL) != pid) {
  }
  return WEXITSTATUS(status);
}

static void drop_caps(void)
{
  struct __user_cap_header_struct cap_hdr = {};
  struct __user_cap_data_struct cap_data[2] = {};
  cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
  cap_hdr.pid = getpid();
  if (syscall(SYS_capget, &cap_hdr, &cap_data))
    exit(1);
  const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
  cap_data[0].effective &= ~drop;
  cap_data[0].permitted &= ~drop;
  cap_data[0].inheritable &= ~drop;
  if (syscall(SYS_capset, &cap_hdr, &cap_data))
    exit(1);
}

static int do_sandbox_none(void)
{
  if (unshare(CLONE_NEWPID)) {
  }
  int pid = fork();
  if (pid != 0)
    return wait_for_loop(pid);
  setup_common();
  sandbox_common();
  drop_caps();
  if (unshare(CLONE_NEWNET)) {
  }
  loop();
  exit(1);
}

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 loop(void)
{
  int i, call, thread;
  for (call = 0; call < 6; 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, 45);
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
}

void execute_call(int call)
{
  switch (call) {
  case 0:
    memcpy((void*)0x20000000, "./file0\000", 8);
    syscall(__NR_mkdir, 0x20000000ul, 0ul);
    break;
  case 1:
    memcpy((void*)0x200000c0,
           "\x3f\x00\xfd\x00\xe0\xbb\xb5\x57\xf3\xb0\xb9\x14\x42\xc3\x79\x98"
           "\x3f\x01\x00\x00\x00\xad\x15\xbe\x14\x4a\x70\xa0\x53\xdf\xcd\xeb"
           "\x98\x7f\xbd\x3c\x23\x6b\xfa\x1c\x25\x1b\x4a\x45\xbf\xe3\x0f\x44"
           "\x4d\xc5\xe3\x14\x65\x8f\x7c\x94\x5f\xa4\xad\xbb\x2c\x92\x49\xdd"
           "\x44\xbe\x32\xdc\x79\xb3\x98\x12\xdd\xa8\x76\x84\x0f\x3f\x97\x1d"
           "\xd7\x5e\x67\x26\x24\xfe\x15\x84\xa5\x3a",
           90);
    syscall(__NR_getsockopt, 0xffffff9c, 0x84, 0x6d, 0x200000c0ul, 0ul);
    break;
  case 2:
    *(uint32_t*)0x2000a000 = 6;
    *(uint32_t*)0x2000a004 = 0x70;
    *(uint8_t*)0x2000a008 = 0;
    *(uint8_t*)0x2000a009 = 0;
    *(uint8_t*)0x2000a00a = 0;
    *(uint8_t*)0x2000a00b = 0;
    *(uint32_t*)0x2000a00c = 0;
    *(uint64_t*)0x2000a010 = 0;
    *(uint64_t*)0x2000a018 = 0;
    *(uint64_t*)0x2000a020 = 0;
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 0, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 1, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 2, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 3, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 4, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 5, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 6, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 7, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 8, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 9, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 10, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 11, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 12, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 13, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 14, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 15, 2);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 17, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 18, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 19, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 20, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 21, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 22, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 23, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 24, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 25, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 26, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 27, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 28, 1);
    STORE_BY_BITMASK(uint64_t, , 0x2000a028, 0, 29, 35);
    *(uint32_t*)0x2000a030 = 0;
    *(uint32_t*)0x2000a034 = 0xf2f97a2d;
    *(uint64_t*)0x2000a038 = 0;
    *(uint64_t*)0x2000a040 = 0;
    *(uint64_t*)0x2000a048 = 0x800000020005221b;
    *(uint64_t*)0x2000a050 = 0x800007f;
    *(uint32_t*)0x2000a058 = 0;
    *(uint32_t*)0x2000a05c = 0;
    *(uint64_t*)0x2000a060 = 0;
    *(uint32_t*)0x2000a068 = 0;
    *(uint16_t*)0x2000a06c = 0;
    *(uint16_t*)0x2000a06e = 0;
    syscall(__NR_perf_event_open, 0x2000a000ul, 0, 0ul, -1, 0ul);
    break;
  case 3:
    memcpy((void*)0x20343ff8, "./file0\000", 8);
    memcpy((void*)0x20fb5ffc, "nfs\000", 4);
    syscall(__NR_mount, 0x20000100ul, 0x20343ff8ul, 0x20fb5ffcul, 0ul,
            0x2000a000ul);
    break;
  case 4:
    syscall(__NR_socket, 0x1dul, 3ul, 1);
    break;
  case 5:
    syscall(__NR_unshare, 0x40000000ul);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  do_sandbox_none();
  return 0;
}