// https://syzkaller.appspot.com/bug?id=4c96204951a296d3cf40fceb6d1969f2bf1d0cbf
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

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

#include <linux/capability.h>

#ifndef __NR_lsetxattr
#define __NR_lsetxattr 227
#endif
#ifndef __NR_mkdirat
#define __NR_mkdirat 296
#endif
#ifndef __NR_mmap
#define __NR_mmap 192
#endif
#ifndef __NR_mount
#define __NR_mount 21
#endif
#undef __NR_mmap
#define __NR_mmap __NR_mmap2

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);
}

void loop(void)
{
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  //  mkdirat arguments: [
  //    fd: fd_dir (resource)
  //    path: ptr[in, buffer] {
  //      buffer: {2e 2f 66 69 6c 65 30 00} (length 0x8)
  //    }
  //    mode: open_mode = 0x1ff (4 bytes)
  //  ]
  memcpy((void*)0x80000100, "./file0\000", 8);
  syscall(
      __NR_mkdirat, /*fd=*/0xffffff9c, /*path=*/0x80000100,
      /*mode=S_IXOTH|S_IWOTH|S_IROTH|S_IXGRP|S_IWGRP|S_IRGRP|S_IXUSR|S_IWUSR|0x100*/
      0x1ff);
  //  mount arguments: [
  //    src: ptr[in, blockdev_filename] {
  //      union blockdev_filename {
  //        filename: buffer: {6d 74 64 30 00} (length 0x5)
  //      }
  //    }
  //    dst: ptr[in, buffer] {
  //      buffer: {2e 2f 66 69 6c 65 30 00} (length 0x8)
  //    }
  //    type: ptr[in, buffer] {
  //      buffer: {6a 66 66 73 32 00} (length 0x6)
  //    }
  //    flags: mount_flags = 0x800000 (4 bytes)
  //    data: nil
  //  ]
  memcpy((void*)0x80000200, "mtd0\000", 5);
  memcpy((void*)0x80000100, "./file0\000", 8);
  memcpy((void*)0x80000300, "jffs2\000", 6);
  syscall(__NR_mount, /*src=*/0x80000200, /*dst=*/0x80000100,
          /*type=*/0x80000300, /*flags=MS_I_VERSION*/ 0x800000, /*data=*/0);
  //  lsetxattr$system_posix_acl arguments: [
  //    path: ptr[in, buffer] {
  //      buffer: {2e 2f 66 69 6c 65 30 00} (length 0x8)
  //    }
  //    name: ptr[in, buffer] {
  //      buffer: {73 79 73 74 65 6d 2e 70 6f 73 69 78 5f 61 63 6c 5f 64 65 66
  //      61 75 6c 74 00} (length 0x19)
  //    }
  //    val: ptr[in, xattr_system_posix_acl_access] {
  //      xattr_system_posix_acl_access {
  //        header: posix_acl_xattr_header {
  //          a_version: const = 0x2 (4 bytes)
  //        }
  //        user_obj: posix_acl_xattr_entry[ACL_USER_OBJ, const[0, int32]] {
  //          e_tag: const = 0x1 (2 bytes)
  //          e_perm: posix_acl_perm = 0x1 (2 bytes)
  //          e_id: const = 0x0 (4 bytes)
  //        }
  //        users: array[posix_acl_xattr_entry[ACL_USER, uid]] {
  //        }
  //        group_obj: posix_acl_xattr_entry[ACL_GROUP_OBJ, const[0, int32]] {
  //          e_tag: const = 0x4 (2 bytes)
  //          e_perm: posix_acl_perm = 0x0 (2 bytes)
  //          e_id: const = 0x0 (4 bytes)
  //        }
  //        groups: array[posix_acl_xattr_entry[ACL_GROUP, gid]] {
  //        }
  //        mask: posix_acl_xattr_entry[ACL_MASK, const[0, int32]] {
  //          e_tag: const = 0x10 (2 bytes)
  //          e_perm: posix_acl_perm = 0x6 (2 bytes)
  //          e_id: const = 0x0 (4 bytes)
  //        }
  //        other: posix_acl_xattr_entry[ACL_OTHER, const[0, int32]] {
  //          e_tag: const = 0x20 (2 bytes)
  //          e_perm: posix_acl_perm = 0x6 (2 bytes)
  //          e_id: const = 0x0 (4 bytes)
  //        }
  //      }
  //    }
  //    size: len = 0x24 (4 bytes)
  //    flags: setxattr_flags = 0x3 (4 bytes)
  //  ]
  memcpy((void*)0x80000800, "./file0\000", 8);
  memcpy((void*)0x800000c0, "system.posix_acl_default\000", 25);
  *(uint32_t*)0x80000e40 = 2;
  *(uint16_t*)0x80000e44 = 1;
  *(uint16_t*)0x80000e46 = 1;
  *(uint32_t*)0x80000e48 = 0;
  *(uint16_t*)0x80000e4c = 4;
  *(uint16_t*)0x80000e4e = 0;
  *(uint32_t*)0x80000e50 = 0;
  *(uint16_t*)0x80000e54 = 0x10;
  *(uint16_t*)0x80000e56 = 6;
  *(uint32_t*)0x80000e58 = 0;
  *(uint16_t*)0x80000e5c = 0x20;
  *(uint16_t*)0x80000e5e = 6;
  *(uint32_t*)0x80000e60 = 0;
  syscall(__NR_lsetxattr, /*path=*/0x80000800, /*name=*/0x800000c0,
          /*val=*/0x80000e40, /*size=*/0x24,
          /*flags=XATTR_REPLACE|XATTR_CREATE*/ 3);
}
int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x7ffff000, /*len=*/0x1000, /*prot=*/0,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32,
          /*fd=*/(intptr_t)-1, /*offset=*/0);
  syscall(__NR_mmap, /*addr=*/0x80000000, /*len=*/0x1000000,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32,
          /*fd=*/(intptr_t)-1, /*offset=*/0);
  syscall(__NR_mmap, /*addr=*/0x81000000, /*len=*/0x1000, /*prot=*/0,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32,
          /*fd=*/(intptr_t)-1, /*offset=*/0);
  const char* reason;
  (void)reason;
  do_sandbox_none();
  return 0;
}