// autogenerated by syzkaller (http://github.com/google/syzkaller)

#ifndef __NR_socket
#define __NR_socket 41
#endif
#ifndef __NR_ioctl
#define __NR_ioctl 16
#endif
#ifndef __NR_syz_emit_ethernet
#define __NR_syz_emit_ethernet 1000006
#endif
#ifndef __NR_connect
#define __NR_connect 42
#endif
#ifndef __NR_sendmmsg
#define __NR_sendmmsg 307
#endif
#ifndef __NR_mmap
#define __NR_mmap 9
#endif

#define _GNU_SOURCE

#include <arpa/inet.h>
#include <errno.h>
#include <fcntl.h>
#include <linux/capability.h>
#include <linux/if.h>
#include <linux/if_ether.h>
#include <linux/if_tun.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <net/if_arp.h>
#include <sched.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/mman.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/wait.h>
#include <unistd.h>

const int kFailStatus = 67;
const int kRetryStatus = 69;

__attribute__((noreturn)) static void doexit(int status)
{
  volatile unsigned i;
  syscall(__NR_exit_group, status);
  for (i = 0;; i++) {
  }
}

__attribute__((noreturn)) static void fail(const char* msg, ...)
{
  int e = errno;
  fflush(stdout);
  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);
}

#define BITMASK_LEN(type, bf_len) (type)((1ull << (bf_len)) - 1)

#define BITMASK_LEN_OFF(type, bf_off, bf_len)                          \
  (type)(BITMASK_LEN(type, (bf_len)) << (bf_off))

#define STORE_BY_BITMASK(type, addr, val, bf_off, bf_len)              \
  if ((bf_off) == 0 && (bf_len) == 0) {                                \
    *(type*)(addr) = (type)(val);                                      \
  } else {                                                             \
    type new_val = *(type*)(addr);                                     \
    new_val &= ~BITMASK_LEN_OFF(type, (bf_off), (bf_len));             \
    new_val |= ((type)(val)&BITMASK_LEN(type, (bf_len))) << (bf_off);  \
    *(type*)(addr) = new_val;                                          \
  }

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)
    fail("tun: snprintf failed");
  if ((size_t)rv >= size)
    fail("tun: string '%s...' doesn't fit into buffer", str);
}

static void snprintf_check(char* str, size_t size, const char* format,
                           ...)
{
  va_list args;

  va_start(args, format);
  vsnprintf_check(str, size, format, args);
  va_end(args);
}

#define COMMAND_MAX_LEN 128

static void execute_command(const char* format, ...)
{
  va_list args;
  char command[COMMAND_MAX_LEN];
  int rv;

  va_start(args, format);

  vsnprintf_check(command, sizeof(command), format, args);
  rv = system(command);
  if (rv != 0)
    fail("tun: command \"%s\" failed with code %d", &command[0], rv);

  va_end(args);
}

static int tunfd = -1;

#define SYZ_TUN_MAX_PACKET_SIZE 1000

#define MAX_PIDS 32
#define ADDR_MAX_LEN 32

#define LOCAL_MAC "aa:aa:aa:aa:aa:%02hx"
#define REMOTE_MAC "bb:bb:bb:bb:bb:%02hx"

#define LOCAL_IPV4 "172.20.%d.170"
#define REMOTE_IPV4 "172.20.%d.187"

#define LOCAL_IPV6 "fe80::%02hxaa"
#define REMOTE_IPV6 "fe80::%02hxbb"

static void initialize_tun(uint64_t pid)
{
  if (pid >= MAX_PIDS)
    fail("tun: no more than %d executors", MAX_PIDS);
  int id = pid;

  tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK);
  if (tunfd == -1)
    fail("tun: can't open /dev/net/tun");

  char iface[IFNAMSIZ];
  snprintf_check(iface, sizeof(iface), "syz%d", id);

  struct ifreq ifr;
  memset(&ifr, 0, sizeof(ifr));
  strncpy(ifr.ifr_name, iface, IFNAMSIZ);
  ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
  if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0)
    fail("tun: ioctl(TUNSETIFF) failed");

  char local_mac[ADDR_MAX_LEN];
  snprintf_check(local_mac, sizeof(local_mac), LOCAL_MAC, id);
  char remote_mac[ADDR_MAX_LEN];
  snprintf_check(remote_mac, sizeof(remote_mac), REMOTE_MAC, id);

  char local_ipv4[ADDR_MAX_LEN];
  snprintf_check(local_ipv4, sizeof(local_ipv4), LOCAL_IPV4, id);
  char remote_ipv4[ADDR_MAX_LEN];
  snprintf_check(remote_ipv4, sizeof(remote_ipv4), REMOTE_IPV4, id);

  char local_ipv6[ADDR_MAX_LEN];
  snprintf_check(local_ipv6, sizeof(local_ipv6), LOCAL_IPV6, id);
  char remote_ipv6[ADDR_MAX_LEN];
  snprintf_check(remote_ipv6, sizeof(remote_ipv6), REMOTE_IPV6, id);

  execute_command("sysctl -w net.ipv6.conf.%s.accept_dad=0", iface);

  execute_command("sysctl -w net.ipv6.conf.%s.router_solicitations=0",
                  iface);

  execute_command("ip link set dev %s address %s", iface, local_mac);
  execute_command("ip addr add %s/24 dev %s", local_ipv4, iface);
  execute_command("ip -6 addr add %s/120 dev %s", local_ipv6, iface);
  execute_command("ip neigh add %s lladdr %s dev %s nud permanent",
                  remote_ipv4, remote_mac, iface);
  execute_command("ip -6 neigh add %s lladdr %s dev %s nud permanent",
                  remote_ipv6, remote_mac, iface);
  execute_command("ip link set dev %s up", iface);
}

static void setup_tun(uint64_t pid, bool enable_tun)
{
  if (enable_tun)
    initialize_tun(pid);
}

struct csum_inet {
  uint32_t acc;
};

static void csum_inet_init(struct csum_inet* csum)
{
  csum->acc = 0;
}

static void csum_inet_update(struct csum_inet* csum,
                             const uint8_t* data, size_t length)
{
  if (length == 0)
    return;

  size_t i;
  for (i = 0; i < length - 1; i += 2)
    csum->acc += *(uint16_t*)&data[i];

  if (length & 1)
    csum->acc += (uint16_t)data[length - 1];

  while (csum->acc > 0xffff)
    csum->acc = (csum->acc & 0xffff) + (csum->acc >> 16);
}

static uint16_t csum_inet_digest(struct csum_inet* csum)
{
  return ~csum->acc;
}

static uintptr_t syz_emit_ethernet(uintptr_t a0, uintptr_t a1)
{

  if (tunfd < 0)
    return (uintptr_t)-1;

  int64_t length = a0;
  char* data = (char*)a1;
  return write(tunfd, data, length);
}

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 = 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);

  unshare(CLONE_NEWNS);
  unshare(CLONE_NEWIPC);
  unshare(CLONE_IO);
}

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) {
    close(fd);
    return false;
  }
  close(fd);
  return true;
}

static int real_uid;
static int real_gid;
static int epid;
static bool etun;
__attribute__((aligned(64 << 10))) static char sandbox_stack[1 << 20];

static int namespace_sandbox_proc(void* arg)
{
  sandbox_common();

  write_file("/proc/self/setgroups", "deny");
  if (!write_file("/proc/self/uid_map", "0 %d 1\n", real_uid))
    fail("write of /proc/self/uid_map failed");
  if (!write_file("/proc/self/gid_map", "0 %d 1\n", real_gid))
    fail("write of /proc/self/gid_map failed");

  setup_tun(epid, etun);

  if (mkdir("./syz-tmp", 0777))
    fail("mkdir(syz-tmp) failed");
  if (mount("", "./syz-tmp", "tmpfs", 0, NULL))
    fail("mount(tmpfs) failed");
  if (mkdir("./syz-tmp/newroot", 0777))
    fail("mkdir failed");
  if (mkdir("./syz-tmp/newroot/dev", 0700))
    fail("mkdir failed");
  if (mount("/dev", "./syz-tmp/newroot/dev", NULL,
            MS_BIND | MS_REC | MS_PRIVATE, NULL))
    fail("mount(dev) failed");
  if (mkdir("./syz-tmp/newroot/proc", 0700))
    fail("mkdir failed");
  if (mount(NULL, "./syz-tmp/newroot/proc", "proc", 0, NULL))
    fail("mount(proc) failed");
  if (mkdir("./syz-tmp/pivot", 0777))
    fail("mkdir failed");
  if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) {
    if (chdir("./syz-tmp"))
      fail("chdir failed");
  } else {
    if (chdir("/"))
      fail("chdir failed");
    if (umount2("./pivot", MNT_DETACH))
      fail("umount failed");
  }
  if (chroot("./newroot"))
    fail("chroot failed");
  if (chdir("/"))
    fail("chdir failed");

  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))
    fail("capget failed");
  cap_data[0].effective &= ~(1 << CAP_SYS_PTRACE);
  cap_data[0].permitted &= ~(1 << CAP_SYS_PTRACE);
  cap_data[0].inheritable &= ~(1 << CAP_SYS_PTRACE);
  if (syscall(SYS_capset, &cap_hdr, &cap_data))
    fail("capset failed");

  loop();
  doexit(1);
}

static int do_sandbox_namespace(int executor_pid, bool enable_tun)
{
  real_uid = getuid();
  real_gid = getgid();
  epid = executor_pid;
  etun = enable_tun;
  mprotect(sandbox_stack, 4096, PROT_NONE);
  return clone(
      namespace_sandbox_proc,
      &sandbox_stack[sizeof(sandbox_stack) - 64],
      CLONE_NEWUSER | CLONE_NEWPID | CLONE_NEWUTS | CLONE_NEWNET, NULL);
}

static void test();

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

long r[128];
void test()
{
  memset(r, -1, sizeof(r));
  r[0] = syscall(__NR_mmap, 0x20000000ul, 0xfff000ul, 0x3ul, 0x32ul,
                 0xfffffffffffffffful, 0x0ul);
  r[1] = syscall(__NR_socket, 0xaul, 0x6ul, 0x0ul);
  memcpy((void*)0x208befe0,
         "\x73\x69\x74\x30\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x00",
         16);
  *(uint16_t*)0x208beff0 = (uint16_t)0x2;
  *(uint16_t*)0x208beff2 = (uint16_t)0x204e;
  *(uint8_t*)0x208beff4 = (uint8_t)0xac;
  *(uint8_t*)0x208beff5 = (uint8_t)0x14;
  *(uint8_t*)0x208beff6 = (uint8_t)0x0;
  *(uint8_t*)0x208beff7 = (uint8_t)0xaa;
  *(uint8_t*)0x208beff8 = (uint8_t)0x0;
  *(uint8_t*)0x208beff9 = (uint8_t)0x0;
  *(uint8_t*)0x208beffa = (uint8_t)0x0;
  *(uint8_t*)0x208beffb = (uint8_t)0x0;
  *(uint8_t*)0x208beffc = (uint8_t)0x0;
  *(uint8_t*)0x208beffd = (uint8_t)0x0;
  *(uint8_t*)0x208beffe = (uint8_t)0x0;
  *(uint8_t*)0x208befff = (uint8_t)0x0;
  r[17] = syscall(__NR_ioctl, r[1], 0x8914ul, 0x208befe0ul);
  *(uint8_t*)0x2000f000 = (uint8_t)0xbb;
  *(uint8_t*)0x2000f001 = (uint8_t)0xbb;
  *(uint8_t*)0x2000f002 = (uint8_t)0xbb;
  *(uint8_t*)0x2000f003 = (uint8_t)0xbb;
  *(uint8_t*)0x2000f004 = (uint8_t)0xbb;
  *(uint8_t*)0x2000f005 = (uint8_t)0x0;
  *(uint8_t*)0x2000f006 = (uint8_t)0x0;
  *(uint8_t*)0x2000f007 = (uint8_t)0x0;
  *(uint8_t*)0x2000f008 = (uint8_t)0x0;
  *(uint8_t*)0x2000f009 = (uint8_t)0x0;
  *(uint8_t*)0x2000f00a = (uint8_t)0x0;
  *(uint8_t*)0x2000f00b = (uint8_t)0x0;
  *(uint16_t*)0x2000f00c = (uint16_t)0xf588;
  STORE_BY_BITMASK(uint8_t, 0x2000f00e, 0xa, 0, 4);
  STORE_BY_BITMASK(uint8_t, 0x2000f00e, 0x4, 4, 4);
  STORE_BY_BITMASK(uint8_t, 0x2000f00f, 0x401, 0, 2);
  STORE_BY_BITMASK(uint8_t, 0x2000f00f, 0x8, 2, 6);
  *(uint16_t*)0x2000f010 = (uint16_t)0x3000;
  *(uint16_t*)0x2000f012 = (uint16_t)0x1fc;
  *(uint16_t*)0x2000f014 = (uint16_t)0x4;
  *(uint8_t*)0x2000f016 = (uint8_t)0x400;
  *(uint8_t*)0x2000f017 = (uint8_t)0x29;
  *(uint16_t*)0x2000f018 = (uint16_t)0x0;
  *(uint32_t*)0x2000f01a = (uint32_t)0x20000e0;
  *(uint32_t*)0x2000f01e = (uint32_t)0x10000e0;
  *(uint8_t*)0x2000f022 = (uint8_t)0x83;
  *(uint8_t*)0x2000f023 = (uint8_t)0x13;
  *(uint8_t*)0x2000f024 = (uint8_t)0x2;
  *(uint32_t*)0x2000f025 = (uint32_t)0x10000e0;
  *(uint32_t*)0x2000f029 = (uint32_t)0x100007f;
  *(uint32_t*)0x2000f02d = (uint32_t)0x1000080;
  *(uint32_t*)0x2000f031 = (uint32_t)0x20000e0;
  *(uint8_t*)0x2000f036 = (uint8_t)0x22;
  *(uint8_t*)0x2000f037 = (uint8_t)0xff;
  *(uint16_t*)0x2000f038 = (uint16_t)0x0;
  *(uint32_t*)0x2000f03a = (uint32_t)0x100007f;
  struct csum_inet csum_54;
  csum_inet_init(&csum_54);
  csum_inet_update(&csum_54, (const uint8_t*)0x2000f036, 8);
  *(uint16_t*)0x2000f038 = csum_inet_digest(&csum_54);
  struct csum_inet csum_55;
  csum_inet_init(&csum_55);
  csum_inet_update(&csum_55, (const uint8_t*)0x2000f00e, 40);
  *(uint16_t*)0x2000f018 = csum_inet_digest(&csum_55);
  r[56] = syz_emit_ethernet(0x3eul, 0x2000f000ul);
  r[57] = syscall(__NR_socket, 0x2ul, 0x806ul, 0x0ul);
  memcpy((void*)0x20dc4000,
         "\x6c\x6f\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x00",
         16);
  *(uint64_t*)0x20dc4010 = (uint64_t)0x4;
  *(uint64_t*)0x20dc4018 = (uint64_t)0xffffffffffffffff;
  *(uint16_t*)0x20dc4020 = (uint16_t)0x2;
  *(uint8_t*)0x20dc4022 = (uint8_t)0x40;
  *(uint8_t*)0x20dc4023 = (uint8_t)0x2ed5;
  *(uint8_t*)0x20dc4024 = (uint8_t)0x8;
  r[65] = syscall(__NR_ioctl, r[57], 0x8922ul, 0x20dc4000ul);
  r[66] = syscall(__NR_socket, 0xaul, 0x3ul, 0x6ul);
  memcpy((void*)0x20334000,
         "\x73\x69\x74\x30\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
         "\x00",
         16);
  *(uint16_t*)0x20334010 = (uint16_t)0x1;
  r[69] = syscall(__NR_ioctl, r[66], 0x8914ul, 0x20334000ul);
  r[70] =
      syscall(__NR_socket, 0xaul, 0x8000000080803ul, 0x200000000fful);
  *(uint16_t*)0x20ffcfe4 = (uint16_t)0xa;
  *(uint16_t*)0x20ffcfe6 = (uint16_t)0x204e;
  *(uint32_t*)0x20ffcfe8 = (uint32_t)0xfffffffffffffffd;
  *(uint64_t*)0x20ffcfec = (uint64_t)0x0;
  *(uint64_t*)0x20ffcff4 = (uint64_t)0x100000000000000;
  *(uint32_t*)0x20ffcffc = (uint32_t)0xfffffffffffffffd;
  r[77] = syscall(__NR_connect, r[70], 0x20ffcfe4ul, 0x1cul);
  *(uint64_t*)0x20fe2f40 = (uint64_t)0x0;
  *(uint32_t*)0x20fe2f48 = (uint32_t)0x0;
  *(uint64_t*)0x20fe2f50 = (uint64_t)0x20736f70;
  *(uint64_t*)0x20fe2f58 = (uint64_t)0x3;
  *(uint64_t*)0x20fe2f60 = (uint64_t)0x20ff3000;
  *(uint64_t*)0x20fe2f68 = (uint64_t)0x0;
  *(uint32_t*)0x20fe2f70 = (uint32_t)0x1;
  *(uint32_t*)0x20fe2f78 = (uint32_t)0x0;
  *(uint64_t*)0x20fe2f80 = (uint64_t)0x20f7efff;
  *(uint32_t*)0x20fe2f88 = (uint32_t)0x0;
  *(uint64_t*)0x20fe2f90 = (uint64_t)0x20642000;
  *(uint64_t*)0x20fe2f98 = (uint64_t)0x2;
  *(uint64_t*)0x20fe2fa0 = (uint64_t)0x20acee40;
  *(uint64_t*)0x20fe2fa8 = (uint64_t)0x4;
  *(uint32_t*)0x20fe2fb0 = (uint32_t)0x400f;
  *(uint32_t*)0x20fe2fb8 = (uint32_t)0x5;
  *(uint64_t*)0x20fe2fc0 = (uint64_t)0x0;
  *(uint32_t*)0x20fe2fc8 = (uint32_t)0x0;
  *(uint64_t*)0x20fe2fd0 = (uint64_t)0x20ff4797;
  *(uint64_t*)0x20fe2fd8 = (uint64_t)0x0;
  *(uint64_t*)0x20fe2fe0 = (uint64_t)0x20f51000;
  *(uint64_t*)0x20fe2fe8 = (uint64_t)0x1;
  *(uint32_t*)0x20fe2ff0 = (uint32_t)0x20008000;
  *(uint32_t*)0x20fe2ff8 = (uint32_t)0x2;
  *(uint64_t*)0x20736f70 = (uint64_t)0x20a4ff16;
  *(uint64_t*)0x20736f78 = (uint64_t)0x0;
  *(uint64_t*)0x20736f80 = (uint64_t)0x20869fff;
  *(uint64_t*)0x20736f88 = (uint64_t)0x0;
  *(uint64_t*)0x20736f90 = (uint64_t)0x20b69000;
  *(uint64_t*)0x20736f98 = (uint64_t)0x0;
  *(uint64_t*)0x20642000 = (uint64_t)0x20aa4000;
  *(uint64_t*)0x20642008 = (uint64_t)0x0;
  *(uint64_t*)0x20642010 = (uint64_t)0x20ff3000;
  *(uint64_t*)0x20642018 = (uint64_t)0x0;
  *(uint64_t*)0x20acee40 = (uint64_t)0x10;
  *(uint32_t*)0x20acee48 = (uint32_t)0x88;
  *(uint32_t*)0x20acee4c = (uint32_t)0x800000006;
  *(uint64_t*)0x20acee50 = (uint64_t)0x10;
  *(uint32_t*)0x20acee58 = (uint32_t)0x108;
  *(uint32_t*)0x20acee5c = (uint32_t)0x9;
  *(uint64_t*)0x20acee60 = (uint64_t)0x10;
  *(uint32_t*)0x20acee68 = (uint32_t)0x11f;
  *(uint32_t*)0x20acee6c = (uint32_t)0x6;
  *(uint64_t*)0x20acee70 = (uint64_t)0x10;
  *(uint32_t*)0x20acee78 = (uint32_t)0x10f;
  *(uint32_t*)0x20acee7c = (uint32_t)0x10001;
  *(uint64_t*)0x20f51000 = (uint64_t)0x10;
  *(uint32_t*)0x20f51008 = (uint32_t)0x1;
  *(uint32_t*)0x20f5100c = (uint32_t)0x7;
  r[127] = syscall(__NR_sendmmsg, r[70], 0x20fe2f40ul, 0x3ul, 0xc0ul);
}

int main()
{
  int pid = do_sandbox_namespace(0, true);
  int status = 0;
  while (waitpid(pid, &status, __WALL) != pid) {
  }
  return 0;
}