// https://syzkaller.appspot.com/bug?id=58798d7b44c848cf6deddf89ef526f9a55989c40
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.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/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 <unistd.h>

#include <linux/capability.h>

static __thread int clone_ongoing;
static __thread int skip_segv;
static __thread jmp_buf segv_env;

static void segv_handler(int sig, siginfo_t* info, void* ctx)
{
  if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) {
    exit(sig);
  }
  uintptr_t addr = (uintptr_t)info->si_addr;
  const uintptr_t prog_start = 1 << 20;
  const uintptr_t prog_end = 100 << 20;
  int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0;
  int valid = addr < prog_start || addr > prog_end;
  if (skip && valid) {
    _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(...)                                                        \
  ({                                                                           \
    int ok = 1;                                                                \
    __atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    if (_setjmp(segv_env) == 0) {                                              \
      __VA_ARGS__;                                                             \
    } else                                                                     \
      ok = 0;                                                                  \
    __atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST);                       \
    ok;                                                                        \
  })

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_gadgetfs();
static void setup_binderfs();
static void setup_fusectl();
static void sandbox_common_mount_tmpfs(void)
{
  write_file("/proc/sys/fs/mount-max", "100000");
  if (mkdir("./syz-tmp", 0777))
    exit(1);
  if (mount("", "./syz-tmp", "tmpfs", 0, NULL))
    exit(1);
  if (mkdir("./syz-tmp/newroot", 0777))
    exit(1);
  if (mkdir("./syz-tmp/newroot/dev", 0700))
    exit(1);
  unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE;
  if (mount("/dev", "./syz-tmp/newroot/dev", NULL, bind_mount_flags, NULL))
    exit(1);
  if (mkdir("./syz-tmp/newroot/proc", 0700))
    exit(1);
  if (mount("syz-proc", "./syz-tmp/newroot/proc", "proc", 0, NULL))
    exit(1);
  if (mkdir("./syz-tmp/newroot/selinux", 0700))
    exit(1);
  const char* selinux_path = "./syz-tmp/newroot/selinux";
  if (mount("/selinux", selinux_path, NULL, bind_mount_flags, NULL)) {
    if (errno != ENOENT)
      exit(1);
    if (mount("/sys/fs/selinux", selinux_path, NULL, bind_mount_flags, NULL) &&
        errno != ENOENT)
      exit(1);
  }
  if (mkdir("./syz-tmp/newroot/sys", 0700))
    exit(1);
  if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL))
    exit(1);
  if (mount("/sys/kernel/debug", "./syz-tmp/newroot/sys/kernel/debug", NULL,
            bind_mount_flags, NULL) &&
      errno != ENOENT)
    exit(1);
  if (mount("/sys/fs/smackfs", "./syz-tmp/newroot/sys/fs/smackfs", NULL,
            bind_mount_flags, NULL) &&
      errno != ENOENT)
    exit(1);
  if (mount("/proc/sys/fs/binfmt_misc",
            "./syz-tmp/newroot/proc/sys/fs/binfmt_misc", NULL, bind_mount_flags,
            NULL) &&
      errno != ENOENT)
    exit(1);
  if (mkdir("./syz-tmp/newroot/syz-inputs", 0700))
    exit(1);
  if (mount("/syz-inputs", "./syz-tmp/newroot/syz-inputs", NULL,
            bind_mount_flags | MS_RDONLY, NULL) &&
      errno != ENOENT)
    exit(1);
  if (mkdir("./syz-tmp/pivot", 0777))
    exit(1);
  if (syscall(SYS_pivot_root, "./syz-tmp", "./syz-tmp/pivot")) {
    if (chdir("./syz-tmp"))
      exit(1);
  } else {
    if (chdir("/"))
      exit(1);
    if (umount2("./pivot", MNT_DETACH))
      exit(1);
  }
  if (chroot("./newroot"))
    exit(1);
  if (chdir("/"))
    exit(1);
  setup_gadgetfs();
  setup_binderfs();
  setup_fusectl();
}

static void setup_gadgetfs()
{
  if (mkdir("/dev/gadgetfs", 0777)) {
  }
  if (mount("gadgetfs", "/dev/gadgetfs", "gadgetfs", 0, NULL)) {
  }
}

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

static void setup_binderfs()
{
  if (mkdir("/dev/binderfs", 0777)) {
  }
  if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) {
  }
  if (symlink("/dev/binderfs", "./binderfs")) {
  }
}

static void loop();

static void sandbox_common()
{
  prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
  if (getppid() == 1)
    exit(1);
  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 = 128 << 20;
  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);
  sandbox_common();
  drop_caps();
  if (unshare(CLONE_NEWNET)) {
  }
  write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535");
  sandbox_common_mount_tmpfs();
  loop();
  exit(1);
}

uint64_t r[2] = {0xffffffffffffffff, 0xffffffffffffffff};

void loop(void)
{
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  //  openat$selinux_load arguments: [
  //    fd: const = 0xffffffffffffff9c (8 bytes)
  //    file: ptr[in, buffer] {
  //      buffer: {2f 73 65 6c 69 6e 75 78 2f 6c 6f 61 64 00} (length 0xe)
  //    }
  //    flags: const = 0x2 (4 bytes)
  //    mode: const = 0x0 (2 bytes)
  //  ]
  //  returns fd_selinux_load
  NONFAILING(memcpy((void*)0x2000000000c0, "/selinux/load\000", 14));
  res = syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul,
                /*file=*/0x2000000000c0ul, /*flags=*/2, /*mode=*/0);
  if (res != -1)
    r[0] = res;
  //  openat$selinux_policy arguments: [
  //    fd: const = 0xffffff9c (8 bytes)
  //    file: ptr[in, buffer] {
  //      buffer: {2f 73 65 6c 69 6e 75 78 2f 70 6f 6c 69 63 79 00} (length
  //      0x10)
  //    }
  //    flags: const = 0x0 (4 bytes)
  //    mode: const = 0x0 (2 bytes)
  //  ]
  //  returns fd
  NONFAILING(memcpy((void*)0x200000001040, "/selinux/policy\000", 16));
  res = syscall(__NR_openat, /*fd=*/0xffffff9cul, /*file=*/0x200000001040ul,
                /*flags=*/0, /*mode=*/0);
  if (res != -1)
    r[1] = res;
  //  mmap arguments: [
  //    addr: VMA[0xb36000]
  //    len: len = 0xb36000 (8 bytes)
  //    prot: mmap_prot = 0x300000b (8 bytes)
  //    flags: mmap_flags = 0x12 (8 bytes)
  //    fd: fd (resource)
  //    offset: intptr = 0x0 (8 bytes)
  //  ]
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0xb36000ul,
          /*prot=PROT_GROWSUP|PROT_GROWSDOWN|PROT_SEM|PROT_WRITE|PROT_READ*/
          0x300000bul, /*flags=MAP_FIXED|MAP_PRIVATE*/ 0x12ul, /*fd=*/r[1],
          /*offset=*/0ul);
  //  openat$binderfs arguments: [
  //    fd: const = 0xffffffffffffff9c (8 bytes)
  //    file: ptr[in, buffer] {
  //      buffer: {2e 2f 62 69 6e 64 65 72 66 73 32 2f 63 75 73 74 6f 6d 30 00}
  //      (length 0x14)
  //    }
  //    flags: binder_open_flags = 0x800 (4 bytes)
  //    mode: const = 0x0 (2 bytes)
  //  ]
  //  returns fd_binder
  NONFAILING(memcpy((void*)0x2000000001c0, "./binderfs2/custom0\000", 20));
  syscall(__NR_openat, /*fd=*/0xffffffffffffff9cul, /*file=*/0x2000000001c0ul,
          /*flags=O_NONBLOCK*/ 0x800, /*mode=*/0);
  //  sendmsg$MPTCP_PM_CMD_GET_ADDR arguments: [
  //    fd: sock_nl_generic (resource)
  //    msg: ptr[in, msghdr_netlink[netlink_msg_t[genl_mptcp_family_id,
  //    genlmsghdr_t[MPTCP_PM_CMD_GET_ADDR], mptcp_pm_policy]]] {
  //      msghdr_netlink[netlink_msg_t[genl_mptcp_family_id,
  //      genlmsghdr_t[MPTCP_PM_CMD_GET_ADDR], mptcp_pm_policy]] {
  //        addr: nil
  //        addrlen: len = 0x0 (4 bytes)
  //        pad = 0x0 (4 bytes)
  //        vec: ptr[in, iovec[in, netlink_msg_t[genl_mptcp_family_id,
  //        genlmsghdr_t[MPTCP_PM_CMD_GET_ADDR], mptcp_pm_policy]]] {
  //          iovec[in, netlink_msg_t[genl_mptcp_family_id,
  //          genlmsghdr_t[MPTCP_PM_CMD_GET_ADDR], mptcp_pm_policy]] {
  //            addr: ptr[inout, array[ANYUNION]] {
  //              array[ANYUNION] {
  //                union ANYUNION {
  //                  ANYBLOB: buffer: {} (length 0x0)
  //                }
  //                union ANYUNION {
  //                  ANYRESDEC: ANYRES64 (resource)
  //                }
  //                union ANYUNION {
  //                  ANYBLOB: buffer: {} (length 0x0)
  //                }
  //              }
  //            }
  //            len: len = 0x18 (8 bytes)
  //          }
  //        }
  //        vlen: const = 0x1 (8 bytes)
  //        ctrl: const = 0x0 (8 bytes)
  //        ctrllen: const = 0x0 (8 bytes)
  //        f: send_flags = 0x4000800 (4 bytes)
  //        pad = 0x0 (4 bytes)
  //      }
  //    }
  //    f: send_flags = 0x804 (8 bytes)
  //  ]
  NONFAILING(*(uint64_t*)0x200000000b80 = 0);
  NONFAILING(*(uint32_t*)0x200000000b88 = 0);
  NONFAILING(*(uint64_t*)0x200000000b90 = 0x200000000b40);
  NONFAILING(*(uint64_t*)0x200000000b40 = 0x200000000200);
  NONFAILING(sprintf((char*)0x200000000200, "%020llu", (long long)-1));
  NONFAILING(*(uint64_t*)0x200000000b48 = 0x18);
  NONFAILING(*(uint64_t*)0x200000000b98 = 1);
  NONFAILING(*(uint64_t*)0x200000000ba0 = 0);
  NONFAILING(*(uint64_t*)0x200000000ba8 = 0);
  NONFAILING(*(uint32_t*)0x200000000bb0 = 0x4000800);
  syscall(__NR_sendmsg, /*fd=*/(intptr_t)-1, /*msg=*/0x200000000b80ul,
          /*f=MSG_DONTROUTE|MSG_CONFIRM*/ 0x804ul);
  //  write$selinux_load arguments: [
  //    fd: fd_selinux_load (resource)
  //    buf: ptr[inout, array[ANYUNION]] {
  //      array[ANYUNION] {
  //      }
  //    }
  //    count: bytesize = 0x2000 (8 bytes)
  //  ]
  syscall(__NR_write, /*fd=*/r[0], /*buf=*/0x200000000000ul,
          /*count=*/0x2000ul);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffffffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200000000000ul, /*len=*/0x1000000ul,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x200001000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
          /*fd=*/(intptr_t)-1, /*offset=*/0ul);
  const char* reason;
  (void)reason;
  install_segv_handler();
  do_sandbox_none();
  return 0;
}