From: Christopher Faulet <cfaulet@haproxy.com>
Date: Thu, 4 Jun 2026 16:55:23 +0000 (+0200)
Subject: BUG/MEDIUM: check: Ignore small-buffer option when starting an external check
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=4b9c8b24c524368e13e15b8e889f9f35c3679c09;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: check: Ignore small-buffer option when starting an external check

When an external check is started for a server, there is no tcpcheck
ruleset. The pointer is NULL. It was an issue leading to a crash if the
small-buffer option was enabled on the healthchecks. However, it is
irrelevant for external checks because it is only usefull to tcp checks.

So, the option must be ignored if there is no tcpcheck ruleset.

This patch must be backported to 3.4.
---

diff --git a/src/check.c b/src/check.c
index be9794680..f3df19077 100644
--- a/src/check.c
+++ b/src/check.c
@@ -1682,7 +1682,7 @@ static int start_checks()
 	for (px = proxies_list; px; px = px->next) {
 		for (s = px->srv; s; s = s->next) {
 			if ((px->options2 & PR_O2_USE_SBUF_CHECK) &&
-			    (s->check.tcpcheck->rs->flags & TCPCHK_RULES_MAY_USE_SBUF))
+			    (s->check.tcpcheck->rs && s->check.tcpcheck->rs->flags & TCPCHK_RULES_MAY_USE_SBUF))
 				s->check.state |= CHK_ST_USE_SMALL_BUFF;
 
 			if (s->check.state & CHK_ST_CONFIGURED) {