dnsdist: Don't cache ServFail / Refused if the TTL is set to 0

diff --git a/pdns/dnsdist-cache.cc b/pdns/dnsdist-cache.cc
index ec3358795fa7a360e1f7898399e1f58dfb92ca35..75ae261df3e070c0f4e5b22806c04a68cd40982c 100644 (file)
--- a/pdns/dnsdist-cache.cc
+++ b/pdns/dnsdist-cache.cc
@@ -53,6 +53,9 @@ void DNSDistPacketCache::insert(uint32_t key, const DNSName& qname, uint16_t qty
 
   if (rcode == RCode::ServFail || rcode == RCode::Refused) {
     minTTL = d_tempFailureTTL;
+    if (minTTL == 0) {
+      return;
+    }
   }
   else {
     minTTL = getMinTTL(response, responseLen);