From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Thu, 28 May 2026 14:44:03 +0000 (+0200)
Subject: BUG/MINOR: mux_quic: fix BE conn removal on app shutdown
X-Git-Tag: v3.4.0~67
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=c76e0f1bc4d1022b93af2a2e677343b63f45a688;p=thirdparty%2Fhaproxy.git

BUG/MINOR: mux_quic: fix BE conn removal on app shutdown

When QUIC application layer is shut for a backend connection, the
connection is immediately removed from its idle pool. This is a nice
optimization as this prevents a future streams to try to reuse an
unusable connection. This is implemented since the following commit.

  00d668549e46b34d29ea3daa1f6dd42b5251a365
  MINOR: mux-quic: do not reuse connection if app already shut

However, this removal is not correctly performed as it is used
conn_delete_from_tree(). For private connections, this can cause crashes
as they are stored in the session instead. Thus, connection status is
now properly check, and alternatively session_unown_conn() is used if
stored in the session.

This must be backported up to 3.3.
---

diff --git a/src/mux_quic.c b/src/mux_quic.c
index 2edc88b78..58c94a1f0 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -3555,8 +3555,12 @@ static void qcc_app_shutdown(struct qcc *qcc)
 	}
 
 	/* A connection is not reusable if app layer is closed. */
-	if (qcc->flags & QC_CF_IS_BACK)
-		conn_delete_from_tree(qcc->conn, tid);
+	if (qcc->flags & QC_CF_IS_BACK) {
+		if (qcc->conn->flags & CO_FL_LIST_MASK)
+			conn_delete_from_tree(qcc->conn, tid);
+		else if (qcc->conn->flags & CO_FL_SESS_IDLE)
+			session_unown_conn(qcc->conn->owner, qcc->conn);
+	}
 
  out:
 	qcc->app_st = QCC_APP_ST_SHUT;