dnsdist: Release incoming TCP connection right away on backend failure

We used to keep a shared pointer to the incoming TCP connection around
in `TCPConnectionToBackend::d_currentQuery.d_sender` even after all queries
sent to the backend failed, which prevented the incoming TCP connection
from being closed as soon as it should have.

diff --git a/pdns/dnsdistdist/dnsdist-tcp-downstream.cc b/pdns/dnsdistdist/dnsdist-tcp-downstream.cc
index 684c46fceee1913ff9aeaf004b32366b50805e41..904913e3eeda61b9c6aba7045edbe21a7819fbb8 100644 (file)
--- a/pdns/dnsdistdist/dnsdist-tcp-downstream.cc
+++ b/pdns/dnsdistdist/dnsdist-tcp-downstream.cc
@@ -608,7 +608,7 @@ void TCPConnectionToBackend::notifyAllQueriesFailed(const struct timeval& now, F
   try {
     if (d_state == State::sendingQueryToBackend) {
       increaseCounters(d_currentQuery.d_query.d_idstate.cs);
-      auto sender = d_currentQuery.d_sender;
+      auto sender = std::move(d_currentQuery.d_sender);
       if (sender->active()) {
         TCPResponse response(std::move(d_currentQuery.d_query));
         sender->notifyIOError(now, std::move(response));
@@ -617,7 +617,7 @@ void TCPConnectionToBackend::notifyAllQueriesFailed(const struct timeval& now, F
 
     for (auto& query : pendingQueries) {
       increaseCounters(query.d_query.d_idstate.cs);
-      auto sender = query.d_sender;
+      auto sender = std::move(query.d_sender);
       if (sender->active()) {
         TCPResponse response(std::move(query.d_query));
         sender->notifyIOError(now, std::move(response));
@@ -626,7 +626,7 @@ void TCPConnectionToBackend::notifyAllQueriesFailed(const struct timeval& now, F
 
     for (auto& response : pendingResponses) {
       increaseCounters(response.second.d_query.d_idstate.cs);
-      auto sender = response.second.d_sender;
+      auto sender = std::move(response.second.d_sender);
       if (sender->active()) {
         TCPResponse tresp(std::move(response.second.d_query));
         sender->notifyIOError(now, std::move(tresp));