From: Remi Gacogne <remi.gacogne@powerdns.com>
Date: Tue, 26 Aug 2025 12:42:38 +0000 (+0200)
Subject: dnsdist: Fix a caching bug when all servers are down and the query was received over TCP
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=1ebc5ce098bb84de81ab6560c5ec2b5bb28d5ed6;p=thirdparty%2Fpdns.git

dnsdist: Fix a caching bug when all servers are down and the query was received over TCP

Signed-off-by: Remi Gacogne <remi.gacogne@powerdns.com>
---

diff --git a/pdns/dnsdistdist/dnsdist.cc b/pdns/dnsdistdist/dnsdist.cc
index 47c5c42ff5..1485f11d13 100644
--- a/pdns/dnsdistdist/dnsdist.cc
+++ b/pdns/dnsdistdist/dnsdist.cc
@@ -1451,8 +1451,8 @@ ProcessQueryResult processQueryAfterRules(DNSQuestion& dnsQuestion, std::shared_
     if (selectedBackend && selectedBackend->isTCPOnly()) {
       willBeForwardedOverUDP = false;
     }
-    else if (!selectedBackend) {
-      willBeForwardedOverUDP = !serverPool.isTCPOnly();
+    else if (!selectedBackend && serverPool.isTCPOnly()) {
+      willBeForwardedOverUDP = false;
     }
 
     uint32_t allowExpired = 0;