From 05619362726a8f4644af4b515c4ed02a5e84539f Mon Sep 17 00:00:00 2001
From: Aram Sargsyan <aram@isc.org>
Date: Wed, 5 Mar 2025 09:58:32 +0000
Subject: [PATCH] Fix a bug in get_request_transport_type()

When dns_remote_done() is true, calling dns_remote_curraddr() asserts.
Add a dns_remote_curraddr() check before calling dns_remote_curraddr().

(cherry picked from commit 6cd9e4f67c48ce9178600aba7fe91266b914e713)
---
 lib/dns/zone.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/dns/zone.c b/lib/dns/zone.c
index 2b1f8393cb..fc170f3bb5 100644
--- a/lib/dns/zone.c
+++ b/lib/dns/zone.c
@@ -18312,7 +18312,9 @@ get_request_transport_type(dns_zone_t *zone) {
 					 : DNS_TRANSPORT_UDP;
 
 		/* Check if the peer is forced to always use TCP. */
-		if (transport_type != DNS_TRANSPORT_TCP) {
+		if (transport_type != DNS_TRANSPORT_TCP &&
+		    !dns_remote_done(&zone->primaries))
+		{
 			isc_result_t result;
 			isc_sockaddr_t primaryaddr;
 			isc_netaddr_t primaryip;