From: Colin Vidal <colin@isc.org>
Date: Fri, 29 May 2026 20:06:30 +0000 (+0200)
Subject: Remove useless TTL override in rctx_referral()
X-Git-Url: http://git.ipfire.org/gitweb/?a=commitdiff_plain;h=d784ab5cd913be9542c71cb322c10ec0bce7bfd5;p=thirdparty%2Fbind9.git

Remove useless TTL override in rctx_referral()

Function `rctx_referral()` used to force the TTL of an NS record with
TTL 0 to be 1.  This has now been removed, as the delegation database
already forces a minimum hard-coded TTL of 1 when the delegation has
a TTL of 0.
---

diff --git a/lib/dns/resolver.c b/lib/dns/resolver.c
index 5dc634a010c..d8ca636d67e 100644
--- a/lib/dns/resolver.c
+++ b/lib/dns/resolver.c
@@ -9469,17 +9469,6 @@ rctx_referral(respctx_t *rctx) {
 		return ISC_R_COMPLETE;
 	}
 
-	/*
-	 * NS rdatasets with 0 TTL cause problems.
-	 * dns_view_findzonecut() will not find them when we
-	 * try to follow the referral, and we'll SERVFAIL
-	 * because the best nameservers are now above QDOMAIN.
-	 * We force the TTL to 1 second to prevent this.
-	 */
-	if (rctx->ns_rdataset->ttl == 0) {
-		rctx->ns_rdataset->ttl = 1;
-	}
-
 	/*
 	 * An NS-based delegation can be cached immediately (i.e. there is no
 	 * DNSSEC validation).