From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Thu, 9 Mar 2023 09:14:28 +0000 (+0100)
Subject: MINOR: mux-quic: ensure CONNECTION_CLOSE is scheduled once per conn
X-Git-Tag: v2.8-dev6~11
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=e2213df9fe5a84288a952bd685a0cafc3d1f6b3c;p=thirdparty%2Fhaproxy.git

MINOR: mux-quic: ensure CONNECTION_CLOSE is scheduled once per conn

Add BUG_ON() statements to ensure qcc_emit_cc()/qcc_emit_cc_app() is not
called more than one time for each connection. This should improve code
resilience of MUX-QUIC and H3 and it will ensure that a scheduled
CONNECTION_CLOSE is not overwritten by another one with a different
error code.

This commit relies on the previous one to ensure all QUIC operations are
not conducted as soon as a CONNECTION_CLOSE has been prepared :
  commit d7fbf458f8a4c5b09cbf0da0208fbad70caaca33
  MINOR: mux-quic: interrupt most operations if CONNECTION_CLOSE scheduled

This should be backported up to 2.7.
---

diff --git a/src/mux_quic.c b/src/mux_quic.c
index 945fd6d5f0..c67432391d 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -31,6 +31,9 @@ static void qcc_emit_cc(struct qcc *qcc, int err)
 {
 	TRACE_ENTER(QMUX_EV_QCC_END, qcc->conn);
 
+	/* This function must not be called multiple times. */
+	BUG_ON(qcc->flags & QC_CF_CC_EMIT);
+
 	TRACE_STATE("set CONNECTION_CLOSE on quic-conn", QMUX_EV_QCC_WAKE, qcc->conn);
 	quic_set_connection_close(qcc->conn->handle.qc, quic_err_transport(err));
 	qcc->flags |= QC_CF_CC_EMIT;
@@ -832,6 +835,9 @@ void qcc_emit_cc_app(struct qcc *qcc, int err, int immediate)
 {
 	TRACE_ENTER(QMUX_EV_QCC_END, qcc->conn);
 
+	/* This function must not be called multiple times after immediate is set. */
+	BUG_ON(qcc->flags & QC_CF_CC_EMIT);
+
 	if (immediate) {
 		quic_set_connection_close(qcc->conn->handle.qc, quic_err_app(err));
 		qcc->flags |= QC_CF_CC_EMIT;