From: Mark Andrews <marka@isc.org>
Date: Mon, 1 Feb 2021 02:05:08 +0000 (+1100)
Subject: Check that there was no OPT record before falling back
X-Git-Tag: v9.17.17~36^2~4
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=a3fda086f7af09271a0261587563b5f36516f40d;p=thirdparty%2Fbind9.git

Check that there was no OPT record before falling back

to plain DNS on FORMERR.
---

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 847ead38a85..ebc7fbc2cfc 100644
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -10005,7 +10005,7 @@ rctx_badserver(respctx_t *rctx, isc_result_t result) {
 		return (ISC_R_SUCCESS);
 	}
 
-	if ((rcode == dns_rcode_formerr) &&
+	if ((rcode == dns_rcode_formerr) && rctx->opt == NULL &&
 	    (rctx->retryopts & DNS_FETCHOPT_NOEDNS0) == 0)
 	{
 		/*
diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index 70528f448b8..6f32655a187 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -13606,7 +13606,7 @@ stub_callback(isc_task_t *task, isc_event_t *event) {
 		if (!DNS_ZONE_FLAG(zone, DNS_ZONEFLG_NOEDNS) &&
 		    (msg->rcode == dns_rcode_servfail ||
 		     msg->rcode == dns_rcode_notimp ||
-		     msg->rcode == dns_rcode_formerr))
+		     (msg->rcode == dns_rcode_formerr && msg->opt == NULL)))
 		{
 			dns_zone_log(zone, ISC_LOG_DEBUG(1),
 				     "refreshing stub: rcode (%.*s) retrying "
@@ -13995,7 +13995,7 @@ refresh_callback(isc_task_t *task, isc_event_t *event) {
 		if (!DNS_ZONE_FLAG(zone, DNS_ZONEFLG_NOEDNS) &&
 		    (msg->rcode == dns_rcode_servfail ||
 		     msg->rcode == dns_rcode_notimp ||
-		     msg->rcode == dns_rcode_formerr))
+		     (msg->rcode == dns_rcode_formerr && msg->opt == NULL)))
 		{
 			dns_zone_log(zone, ISC_LOG_DEBUG(1),
 				     "refresh: rcode (%.*s) retrying without "