message: Check that the upstreamHost existst and return an error.
diff: @@ -1431,7 +1431,11 @@ uint32_t Context::getDestinationPort(StreamType type) {
  auto streamInfo = getConstStreamInfo(StreamType2MetadataType(type));
  if (!streamInfo)
  return 0;
  - auto address = streamInfo->upstreamHost()->address();
  + auto host = streamInfo->upstreamHost();
  + if (!host) {
  + return 0;
  + }
  + auto address = host->address();
  if (!address) {
  return 0;
  }
  