// https://syzkaller.appspot.com/bug?id=6dcd14a729df98f989c7b76d254226ae67084efd
// autogenerated by syzkaller (http://github.com/google/syzkaller)

#define _GNU_SOURCE
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <fcntl.h>
#include <linux/capability.h>
#include <sched.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdio.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/stat.h>
#include <sys/stat.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 <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.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);
}

#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;                                                  \
  }

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 __thread int skip_segv;
static __thread jmp_buf segv_env;

static void segv_handler(int sig, siginfo_t* info, void* uctx)
{
  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);
  }
  doexit(sig);
}

static void install_segv_handler()
{
  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 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 uintptr_t syz_open_dev(uintptr_t a0, uintptr_t a1, uintptr_t a2)
{
  if (a0 == 0xc || a0 == 0xb) {
    char buf[128];
    sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1,
            (uint8_t)a2);
    return open(buf, O_RDWR, 0);
  } else {
    char buf[1024];
    char* hash;
    NONFAILING(strncpy(buf, (char*)a0, sizeof(buf)));
    buf[sizeof(buf) - 1] = 0;
    while ((hash = strchr(buf, '#'))) {
      *hash = '0' + (char)(a1 % 10);
      a1 /= 10;
    }
    return open(buf, a2, 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 = 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 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;
__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");

  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)
{
  int pid;

  real_uid = getuid();
  real_gid = getgid();
  mprotect(sandbox_stack, 4096, PROT_NONE);
  pid =
      clone(namespace_sandbox_proc, &sandbox_stack[sizeof(sandbox_stack) - 64],
            CLONE_NEWUSER | CLONE_NEWPID, NULL);
  if (pid < 0)
    fail("sandbox clone failed");
  return pid;
}

static void test();

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

#ifndef __NR_mmap
#define __NR_mmap 192
#endif
#ifndef __NR_write
#define __NR_write 4
#endif
#ifndef __NR_readv
#define __NR_readv 145
#endif
#undef __NR_mmap
#define __NR_mmap __NR_mmap2

long r[1];
uint64_t procid;
void test()
{
  memset(r, -1, sizeof(r));
  syscall(__NR_mmap, 0x20000000, 0xfff000, 3, 0x32, -1, 0);
  NONFAILING(memcpy((void*)0x2002a000, "/dev/sg#", 9));
  r[0] = syz_open_dev(0x2002a000, 0, 0x142);
  NONFAILING(*(uint8_t*)0x205c3000 = 0);
  NONFAILING(*(uint8_t*)0x205c3001 = 0);
  NONFAILING(*(uint16_t*)0x205c3002 = 0);
  NONFAILING(*(uint16_t*)0x205c3004 = 0);
  NONFAILING(*(uint16_t*)0x205c3006 = 2);
  NONFAILING(*(uint16_t*)0x205c3008 = 0);
  NONFAILING(STORE_BY_BITMASK(uint8_t, 0x205c300a, 0, 0, 4));
  NONFAILING(STORE_BY_BITMASK(uint8_t, 0x205c300a, 6, 4, 4));
  NONFAILING(memcpy((void*)0x205c300b, "\xde\x57\x29", 3));
  NONFAILING(*(uint16_t*)0x205c300e = htobe16(0x60));
  NONFAILING(*(uint8_t*)0x205c3010 = 0);
  NONFAILING(*(uint8_t*)0x205c3011 = 0);
  NONFAILING(*(uint8_t*)0x205c3012 = 0xfe);
  NONFAILING(*(uint8_t*)0x205c3013 = 0x80);
  NONFAILING(*(uint8_t*)0x205c3014 = 0);
  NONFAILING(*(uint8_t*)0x205c3015 = 0);
  NONFAILING(*(uint8_t*)0x205c3016 = 0);
  NONFAILING(*(uint8_t*)0x205c3017 = 0);
  NONFAILING(*(uint8_t*)0x205c3018 = 0);
  NONFAILING(*(uint8_t*)0x205c3019 = 0);
  NONFAILING(*(uint8_t*)0x205c301a = 0);
  NONFAILING(*(uint8_t*)0x205c301b = 0);
  NONFAILING(*(uint8_t*)0x205c301c = 0);
  NONFAILING(*(uint8_t*)0x205c301d = 0);
  NONFAILING(*(uint8_t*)0x205c301e = 0);
  NONFAILING(*(uint8_t*)0x205c301f = 0);
  NONFAILING(*(uint8_t*)0x205c3020 = 0 + procid * 1);
  NONFAILING(*(uint8_t*)0x205c3021 = 0xbb);
  NONFAILING(*(uint8_t*)0x205c3022 = 0xfe);
  NONFAILING(*(uint8_t*)0x205c3023 = 0x80);
  NONFAILING(*(uint8_t*)0x205c3024 = 0);
  NONFAILING(*(uint8_t*)0x205c3025 = 0);
  NONFAILING(*(uint8_t*)0x205c3026 = 0);
  NONFAILING(*(uint8_t*)0x205c3027 = 0);
  NONFAILING(*(uint8_t*)0x205c3028 = 0);
  NONFAILING(*(uint8_t*)0x205c3029 = 0);
  NONFAILING(*(uint8_t*)0x205c302a = 0);
  NONFAILING(*(uint8_t*)0x205c302b = 0);
  NONFAILING(*(uint8_t*)0x205c302c = 0);
  NONFAILING(*(uint8_t*)0x205c302d = 0);
  NONFAILING(*(uint8_t*)0x205c302e = 0);
  NONFAILING(*(uint8_t*)0x205c302f = 0);
  NONFAILING(*(uint8_t*)0x205c3030 = 0 + procid * 1);
  NONFAILING(*(uint8_t*)0x205c3031 = 0xaa);
  NONFAILING(*(uint8_t*)0x205c3032 = 0);
  NONFAILING(*(uint8_t*)0x205c3033 = 0);
  NONFAILING(*(uint8_t*)0x205c3034 = 0);
  NONFAILING(*(uint8_t*)0x205c3035 = 0);
  NONFAILING(*(uint8_t*)0x205c3036 = 0);
  NONFAILING(*(uint8_t*)0x205c3037 = 0);
  NONFAILING(*(uint8_t*)0x205c3038 = 0);
  NONFAILING(*(uint8_t*)0x205c3039 = 0);
  NONFAILING(*(uint16_t*)0x205c303a = htobe16(0x4e20 + procid * 4));
  NONFAILING(*(uint16_t*)0x205c303c = htobe16(0x4e21 + procid * 4));
  NONFAILING(*(uint32_t*)0x205c303e = 0x42424242);
  NONFAILING(*(uint32_t*)0x205c3042 = 0x42424242);
  NONFAILING(STORE_BY_BITMASK(uint8_t, 0x205c3046, 0, 0, 1));
  NONFAILING(STORE_BY_BITMASK(uint8_t, 0x205c3046, 0, 1, 3));
  NONFAILING(STORE_BY_BITMASK(uint8_t, 0x205c3046, 0x16, 4, 4));
  NONFAILING(*(uint8_t*)0x205c3047 = 0);
  NONFAILING(*(uint16_t*)0x205c3048 = htobe16(0));
  NONFAILING(*(uint16_t*)0x205c304a = 0);
  NONFAILING(*(uint16_t*)0x205c304c = htobe16(0));
  NONFAILING(*(uint8_t*)0x205c304e = 5);
  NONFAILING(*(uint8_t*)0x205c304f = 0x26);
  NONFAILING(*(uint32_t*)0x205c3050 = htobe32(0x800));
  NONFAILING(*(uint32_t*)0x205c3054 = htobe32(9));
  NONFAILING(*(uint32_t*)0x205c3058 = htobe32(1));
  NONFAILING(*(uint32_t*)0x205c305c = htobe32(0x1f));
  NONFAILING(*(uint32_t*)0x205c3060 = htobe32(0x41));
  NONFAILING(*(uint32_t*)0x205c3064 = htobe32(5));
  NONFAILING(*(uint32_t*)0x205c3068 = htobe32(0x10001));
  NONFAILING(*(uint32_t*)0x205c306c = htobe32(4));
  NONFAILING(*(uint32_t*)0x205c3070 = htobe32(0x101));
  NONFAILING(*(uint8_t*)0x205c3074 = 2);
  NONFAILING(*(uint8_t*)0x205c3075 = 4);
  NONFAILING(*(uint16_t*)0x205c3076 = 0xac1);
  NONFAILING(*(uint8_t*)0x205c3078 = 0xfe);
  NONFAILING(*(uint8_t*)0x205c3079 = 2);
  NONFAILING(*(uint8_t*)0x205c307a = 0);
  NONFAILING(*(uint8_t*)0x205c307b = 0x13);
  NONFAILING(*(uint8_t*)0x205c307c = 0x12);
  NONFAILING(memcpy(
      (void*)0x205c307d,
      "\x40\x08\x07\xe3\xee\xe9\xb1\x73\xb4\x08\x11\x5e\xf4\x5c\x5e\x18", 16));
  NONFAILING(*(uint8_t*)0x205c308d = 3);
  NONFAILING(*(uint8_t*)0x205c308e = 3);
  NONFAILING(*(uint8_t*)0x205c308f = 6);
  struct csum_inet csum_1;
  csum_inet_init(&csum_1);
  NONFAILING(csum_inet_update(&csum_1, (const uint8_t*)0x205c3012, 16));
  NONFAILING(csum_inet_update(&csum_1, (const uint8_t*)0x205c3022, 16));
  uint32_t csum_1_chunk_2 = 0x58000000;
  csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_2, 4);
  uint32_t csum_1_chunk_3 = 0x6000000;
  csum_inet_update(&csum_1, (const uint8_t*)&csum_1_chunk_3, 4);
  NONFAILING(csum_inet_update(&csum_1, (const uint8_t*)0x205c303a, 88));
  NONFAILING(*(uint16_t*)0x205c304a = csum_inet_digest(&csum_1));
  syscall(__NR_write, r[0], 0x205c3000, 0x92);
  NONFAILING(*(uint32_t*)0x206e4000 = 0x20c7d000);
  NONFAILING(*(uint32_t*)0x206e4004 = 0xb7);
  syscall(__NR_readv, r[0], 0x206e4000, 1);
}

int main()
{
  char* cwd = get_current_dir_name();
  for (procid = 0; procid < 8; procid++) {
    if (fork() == 0) {
      install_segv_handler();
      for (;;) {
        if (chdir(cwd))
          fail("failed to chdir");
        use_temporary_dir();
        int pid = do_sandbox_namespace(procid, false);
        int status = 0;
        while (waitpid(pid, &status, __WALL) != pid) {
        }
      }
    }
  }
  sleep(1000000);
  return 0;
}