ResourceDispatcherHostImpl::HttpAuthRelationTypeOf(
    const GURL& request_url,
    const GURL& first_party) {
  if (!first_party.is_valid())
    return HTTP_AUTH_RELATION_TOP;

  if (net::registry_controlled_domains::SameDomainOrHost(
          first_party, request_url,
          net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES))
    return HTTP_AUTH_RELATION_SAME_DOMAIN;

  if (allow_cross_origin_auth_prompt())
    return HTTP_AUTH_RELATION_ALLOWED_CROSS;

  return HTTP_AUTH_RELATION_BLOCKED_CROSS;
}

The product contains a concurrent code sequence that requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence operating concurrently.