// https://syzkaller.appspot.com/bug?id=42a641dd303d7d624a19371a24eb958f2643b718
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <fcntl.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

static long syz_open_procfs(volatile long a0, volatile long a1)
{
  char buf[128];
  memset(buf, 0, sizeof(buf));
  if (a0 == 0) {
    snprintf(buf, sizeof(buf), "/proc/self/%s", (char*)a1);
  } else if (a0 == -1) {
    snprintf(buf, sizeof(buf), "/proc/thread-self/%s", (char*)a1);
  } else {
    snprintf(buf, sizeof(buf), "/proc/self/task/%d/%s", (int)a0, (char*)a1);
  }
  int fd = open(buf, O_RDWR);
  if (fd == -1)
    fd = open(buf, O_RDONLY);
  return fd;
}

uint64_t r[1] = {0xffffffffffffffff};

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;
  intptr_t res = 0;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  //  syz_open_procfs$userns arguments: [
  //    pid: pid (resource)
  //    file: ptr[in, buffer] {
  //      buffer: {6e 73 2f 75 73 65 72 00} (length 0x8)
  //    }
  //  ]
  //  returns fd_userns
  memcpy((void*)0x2000000001c0, "ns/user\000", 8);
  res = -1;
  res = syz_open_procfs(/*pid=*/0, /*file=*/0x2000000001c0);
  if (res != -1)
    r[0] = res;
  //  open_by_handle_at arguments: [
  //    mountdirfd: fd (resource)
  //    handle: ptr[in, file_handle] {
  //      union file_handle {
  //        ceph_nfs_confh: file_handle_t[FILEID_INO32_GEN_PARENT,
  //        ceph_nfs_confh] {
  //          handle_bytes: bytesize = 0x10 (4 bytes)
  //          handle_type: const = 0xf1 (4 bytes)
  //          f_handle: ceph_nfs_confh {
  //            ino: int64 = 0x1002 (8 bytes)
  //            parent_ino: int64 = 0x10000000 (8 bytes)
  //          }
  //        }
  //      }
  //    }
  //    flags: open_flags = 0x400040 (8 bytes)
  //  ]
  *(uint32_t*)0x200000000000 = 0x10;
  *(uint32_t*)0x200000000004 = 0xf1;
  *(uint64_t*)0x200000000008 = 0x1002;
  *(uint64_t*)0x200000000010 = 0x10000000;
  syscall(__NR_open_by_handle_at, /*mountdirfd=*/r[0],
          /*handle=*/0x200000000000ul,
          /*flags=__O_TMPFILE|O_CREAT*/ 0x400040ul);
  return 0;
}