From 0e40fda16a098a438b4508b2d607ca87c411da9e Mon Sep 17 00:00:00 2001
From: Emeric Brun <ebrun@haproxy.com>
Date: Mon, 15 Feb 2021 15:13:31 +0100
Subject: [PATCH] BUG/MINOR: dns: fix ring attach control on dns_session_new

Ths patch adds a control on ring_attach which can not currently fail
since we are the first to try to attach.

This should fix issue #1126
---
 src/dns.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/dns.c b/src/dns.c
index 9e44dd6c4..58c68d75b 100644
--- a/src/dns.c
+++ b/src/dns.c
@@ -1033,7 +1033,13 @@ struct dns_session *dns_session_new(struct dns_stream_server *dss)
 		goto error;
 
 	ring_init(&ds->ring, ds->tx_ring_area, DNS_TCP_MSG_RING_MAX_SIZE);
-	ring_attach(&ds->ring);
+	if (!ring_attach(&ds->ring)) {
+		/* Should never happen
+		 * since we are the first attached
+		 * here
+		 */
+		goto error;
+	}
 
 	if ((ds->task_exp = task_new(tid_bit)) == NULL)
 		goto error;