libnetwork: ServeDNS(): don't panic on unsupported query types

This was added in b3c883b, but resulted in a panic if the embedded DNS had to handle an unsupported query-type, such as ANY. This patch adds a debug log for this case (to better describe how it's handled. Signed-off-by: Sebastiaan van Stijn <[email protected]>
flavio · Oct 14, 2021 · 9a09448 · 9a09448
1 parent 4e6dbb3
commit 9a09448
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/libnetwork/resolver.go b/libnetwork/resolver.go
@@ -384,7 +384,8 @@ func (r *resolver) ServeDNS(w dns.ResponseWriter, query *dns.Msg) {
 	case dns.TypeSRV:
 		resp, err = r.handleSRVQuery(name, query)
 	default:
-		panic("error")
+		queryType := dns.TypeToString[query.Question[0].Qtype]
+		logrus.Debugf("[resolver] query type %s is not supported by the embedded DNS and will be forwarded to external DNS", queryType)
 	}
 
 	if err != nil {