message: null upstream host
diff: @@ -1194,7 +1194,7 @@ WasmResult Context::getProperty(absl::string_view path, std::string* result) {
  value = CelValue::CreateMessage(plugin_->listener_metadata_, &arena);
  break;
  case PropertyToken::CLUSTER_NAME:
  - if (!info->upstreamHost()->cluster().name().empty()) {
  + if (info->upstreamHost() && !info->upstreamHost()->cluster().name().empty()) {
  value = CelValue::CreateString(&info->upstreamHost()->cluster().name());
  } else if (info->routeEntry()) {
  value = CelValue::CreateString(&info->routeEntry()->clusterName());
  