// https://syzkaller.appspot.com/bug?id=036c44ec5b8a6422d1db2a7053a2effb46d81228
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <arpa/inet.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <net/if_arp.h>
#include <pthread.h>
#include <sched.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/ioctl.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/futex.h>
#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_tun.h>
#include <linux/ip.h>
#include <linux/tcp.h>

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_handler = SIG_IGN;
  syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8);
  syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8);
  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 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 thread_start(void* (*fn)(void*), void* arg)
{
  pthread_t th;
  pthread_attr_t attr;
  pthread_attr_init(&attr);
  pthread_attr_setstacksize(&attr, 128 << 10);
  if (pthread_create(&th, &attr, fn, arg))
    exit(1);
  pthread_attr_destroy(&attr);
}

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);
}

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_RELAXED))
      return 1;
    now = current_time_ms();
    if (now - start > timeout)
      return 0;
  }
}

static void vsnprintf_check(char* str, size_t size, const char* format,
                            va_list args)
{
  int rv;
  rv = vsnprintf(str, size, format, args);
  if (rv < 0)
    exit(1);
  if ((size_t)rv >= size)
    exit(1);
}

#define COMMAND_MAX_LEN 128
#define PATH_PREFIX                                                            \
  "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin "
#define PATH_PREFIX_LEN (sizeof(PATH_PREFIX) - 1)

static void execute_command(bool panic, const char* format, ...)
{
  va_list args;
  char command[PATH_PREFIX_LEN + COMMAND_MAX_LEN];
  int rv;
  va_start(args, format);
  memcpy(command, PATH_PREFIX, PATH_PREFIX_LEN);
  vsnprintf_check(command + PATH_PREFIX_LEN, COMMAND_MAX_LEN, format, args);
  va_end(args);
  rv = system(command);
  if (rv) {
    if (panic)
      exit(1);
  }
}

static int tunfd = -1;
static int tun_frags_enabled;
#define SYZ_TUN_MAX_PACKET_SIZE 1000

#define TUN_IFACE "syz_tun"

#define LOCAL_MAC "aa:aa:aa:aa:aa:aa"
#define REMOTE_MAC "aa:aa:aa:aa:aa:bb"

#define LOCAL_IPV4 "172.20.20.170"
#define REMOTE_IPV4 "172.20.20.187"

#define LOCAL_IPV6 "fe80::aa"
#define REMOTE_IPV6 "fe80::bb"

#define IFF_NAPI 0x0010
#define IFF_NAPI_FRAGS 0x0020

static void initialize_tun(void)
{
  tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK);
  if (tunfd == -1) {
    printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n");
    printf("otherwise fuzzing or reproducing might not work as intended\n");
    return;
  }
  const int kTunFd = 240;
  if (dup2(tunfd, kTunFd) < 0)
    exit(1);
  close(tunfd);
  tunfd = kTunFd;
  struct ifreq ifr;
  memset(&ifr, 0, sizeof(ifr));
  strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ);
  ifr.ifr_flags = IFF_TAP | IFF_NO_PI | IFF_NAPI | IFF_NAPI_FRAGS;
  if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) {
    ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
    if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0)
      exit(1);
  }
  if (ioctl(tunfd, TUNGETIFF, (void*)&ifr) < 0)
    exit(1);
  tun_frags_enabled = (ifr.ifr_flags & IFF_NAPI_FRAGS) != 0;
  execute_command(0, "sysctl -w net.ipv6.conf.%s.accept_dad=0", TUN_IFACE);
  execute_command(0, "sysctl -w net.ipv6.conf.%s.router_solicitations=0",
                  TUN_IFACE);
  execute_command(1, "ip link set dev %s address %s", TUN_IFACE, LOCAL_MAC);
  execute_command(1, "ip addr add %s/24 dev %s", LOCAL_IPV4, TUN_IFACE);
  execute_command(1, "ip neigh add %s lladdr %s dev %s nud permanent",
                  REMOTE_IPV4, REMOTE_MAC, TUN_IFACE);
  execute_command(0, "ip -6 addr add %s/120 dev %s", LOCAL_IPV6, TUN_IFACE);
  execute_command(0, "ip -6 neigh add %s lladdr %s dev %s nud permanent",
                  REMOTE_IPV6, REMOTE_MAC, TUN_IFACE);
  execute_command(1, "ip link set dev %s up", TUN_IFACE);
}

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 = 160 << 20;
  setrlimit(RLIMIT_AS, &rlim);
  rlim.rlim_cur = rlim.rlim_max = 8 << 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 (unshare(CLONE_NEWIPC)) {
  }
  if (unshare(0x02000000)) {
  }
  if (unshare(CLONE_NEWUTS)) {
  }
  if (unshare(CLONE_SYSVSEM)) {
  }
}

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

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();
  if (unshare(CLONE_NEWNET)) {
  }
  initialize_tun();
  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;
  int collide = 0;
again:
  for (call = 0; call < 10; 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);
      if (collide && (call % 2) == 0)
        break;
      event_timedwait(&th->done, 45);
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
  if (!collide) {
    collide = 1;
    goto again;
  }
}

uint64_t r[4] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff,
                 0xffffffffffffffff};

void execute_call(int call)
{
  long res;
  switch (call) {
  case 0:
    res = syscall(__NR_socket, 0xa, 2, 0);
    if (res != -1)
      r[0] = res;
    break;
  case 1:
    syscall(__NR_ioctl, -1, 0xae60);
    break;
  case 2:
    syscall(__NR_msgget, 0, 0);
    break;
  case 3:
    NONFAILING(*(uint16_t*)0x20000000 = 0xa);
    NONFAILING(*(uint16_t*)0x20000002 = htobe16(0x4e21));
    NONFAILING(*(uint32_t*)0x20000004 = 0);
    NONFAILING(*(uint8_t*)0x20000008 = 0xfe);
    NONFAILING(*(uint8_t*)0x20000009 = 0x80);
    NONFAILING(*(uint8_t*)0x2000000a = 0);
    NONFAILING(*(uint8_t*)0x2000000b = 0);
    NONFAILING(*(uint8_t*)0x2000000c = 0);
    NONFAILING(*(uint8_t*)0x2000000d = 0);
    NONFAILING(*(uint8_t*)0x2000000e = 0);
    NONFAILING(*(uint8_t*)0x2000000f = 0);
    NONFAILING(*(uint8_t*)0x20000010 = 0);
    NONFAILING(*(uint8_t*)0x20000011 = 0);
    NONFAILING(*(uint8_t*)0x20000012 = 0);
    NONFAILING(*(uint8_t*)0x20000013 = 0);
    NONFAILING(*(uint8_t*)0x20000014 = 0);
    NONFAILING(*(uint8_t*)0x20000015 = 0);
    NONFAILING(*(uint8_t*)0x20000016 = 0);
    NONFAILING(*(uint8_t*)0x20000017 = 0xbb);
    NONFAILING(*(uint32_t*)0x20000018 = 3);
    syscall(__NR_connect, r[0], 0x20000000, 0x1c);
    break;
  case 4:
    NONFAILING(memcpy((void*)0x20000380, "/dev/infiniband/rdma_cm", 24));
    res = syscall(__NR_openat, 0xffffffffffffff9c, 0x20000380, 2, 0);
    if (res != -1)
      r[1] = res;
    break;
  case 5:
    NONFAILING(memcpy((void*)0x200003c0, "/dev/hwrng", 11));
    res = syscall(__NR_openat, 0xffffffffffffff9c, 0x200003c0, 0x102, 0);
    if (res != -1)
      r[2] = res;
    break;
  case 6:
    syscall(__NR_ioctl, r[2], 0x7706, 0x20000400);
    break;
  case 7:
    NONFAILING(*(uint32_t*)0x200005c0 = 0x18);
    NONFAILING(*(uint32_t*)0x200005c4 = 0xfffffffe);
    NONFAILING(*(uint64_t*)0x200005c8 = 3);
    NONFAILING(*(uint32_t*)0x200005d0 = 0xa1c);
    NONFAILING(*(uint32_t*)0x200005d4 = 0);
    syscall(__NR_write, r[2], 0x200005c0, 0x18);
    break;
  case 8:
    NONFAILING(*(uint32_t*)0x20000080 = 0);
    NONFAILING(*(uint16_t*)0x20000084 = 0x18);
    NONFAILING(*(uint16_t*)0x20000086 = 0xfa00);
    NONFAILING(*(uint64_t*)0x20000088 = 0);
    NONFAILING(*(uint64_t*)0x20000090 = 0x20000040);
    NONFAILING(*(uint16_t*)0x20000098 = 0x13f);
    NONFAILING(*(uint8_t*)0x2000009a = 0);
    NONFAILING(*(uint8_t*)0x2000009b = 0);
    NONFAILING(*(uint8_t*)0x2000009c = 0);
    NONFAILING(*(uint8_t*)0x2000009d = 0);
    NONFAILING(*(uint8_t*)0x2000009e = 0);
    NONFAILING(*(uint8_t*)0x2000009f = 0);
    res = syscall(__NR_write, r[1], 0x20000080, 0x12d);
    if (res != -1)
      NONFAILING(r[3] = *(uint32_t*)0x20000040);
    break;
  case 9:
    NONFAILING(*(uint32_t*)0x20000200 = 3);
    NONFAILING(*(uint16_t*)0x20000204 = 0x40);
    NONFAILING(*(uint16_t*)0x20000206 = 0xfa00);
    NONFAILING(*(uint16_t*)0x20000208 = 0xa);
    NONFAILING(*(uint16_t*)0x2000020a = htobe16(0x4e21));
    NONFAILING(*(uint32_t*)0x2000020c = 0);
    NONFAILING(*(uint8_t*)0x20000210 = 0);
    NONFAILING(*(uint8_t*)0x20000211 = 0);
    NONFAILING(*(uint8_t*)0x20000212 = 0);
    NONFAILING(*(uint8_t*)0x20000213 = 0);
    NONFAILING(*(uint8_t*)0x20000214 = 0);
    NONFAILING(*(uint8_t*)0x20000215 = 0);
    NONFAILING(*(uint8_t*)0x20000216 = 0);
    NONFAILING(*(uint8_t*)0x20000217 = 0);
    NONFAILING(*(uint8_t*)0x20000218 = 0);
    NONFAILING(*(uint8_t*)0x20000219 = 0);
    NONFAILING(*(uint8_t*)0x2000021a = 0);
    NONFAILING(*(uint8_t*)0x2000021b = 0);
    NONFAILING(*(uint8_t*)0x2000021c = 0);
    NONFAILING(*(uint8_t*)0x2000021d = 0);
    NONFAILING(*(uint8_t*)0x2000021e = 0);
    NONFAILING(*(uint8_t*)0x2000021f = 0);
    NONFAILING(*(uint32_t*)0x20000220 = 0);
    NONFAILING(*(uint16_t*)0x20000224 = 0xa);
    NONFAILING(*(uint16_t*)0x20000226 = htobe16(0x4e24));
    NONFAILING(*(uint32_t*)0x20000228 = 0);
    NONFAILING(*(uint8_t*)0x2000022c = -1);
    NONFAILING(*(uint8_t*)0x2000022d = 1);
    NONFAILING(*(uint8_t*)0x2000022e = 0);
    NONFAILING(*(uint8_t*)0x2000022f = 0);
    NONFAILING(*(uint8_t*)0x20000230 = 0);
    NONFAILING(*(uint8_t*)0x20000231 = 0);
    NONFAILING(*(uint8_t*)0x20000232 = 0);
    NONFAILING(*(uint8_t*)0x20000233 = 0);
    NONFAILING(*(uint8_t*)0x20000234 = 0);
    NONFAILING(*(uint8_t*)0x20000235 = 0);
    NONFAILING(*(uint8_t*)0x20000236 = 0);
    NONFAILING(*(uint8_t*)0x20000237 = 0);
    NONFAILING(*(uint8_t*)0x20000238 = 0);
    NONFAILING(*(uint8_t*)0x20000239 = 0);
    NONFAILING(*(uint8_t*)0x2000023a = 0);
    NONFAILING(*(uint8_t*)0x2000023b = 1);
    NONFAILING(*(uint32_t*)0x2000023c = 0);
    NONFAILING(*(uint32_t*)0x20000240 = r[3]);
    NONFAILING(*(uint32_t*)0x20000244 = 0);
    syscall(__NR_write, r[1], 0x20000200, 0x48);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  install_segv_handler();
  use_temporary_dir();
  do_sandbox_none();
  return 0;
}