Language: C
Label: vulnerable
CWE: CWE-22 \u2014 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

Code:
static void fio_cluster_listen_on_close(intptr_t uuid,
                                        fio_protocol_s *protocol) {
  free(protocol);
  cluster_data.uuid = -1;
  if (fio_parent_pid() == getpid()) {
#if DEBUG
    FIO_LOG_DEBUG("(%d) stopped listening for cluster connections",
                  (int)getpid());
#endif
    if (fio_data->active)
      fio_stop();
  }
  (void)uuid;
}