From: Christopher Faulet <cfaulet@haproxy.com>
Date: Wed, 12 Apr 2023 16:35:18 +0000 (+0200)
Subject: BUG/MEDIUM: stconn: Do nothing in sc_conn_recv() when the SC needs more room
X-Git-Tag: v2.8-dev8~161
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=95125886ee2599c9d65c49651a665734bbc5a0fd;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: stconn: Do nothing in sc_conn_recv() when the SC needs more room

We erroneously though that an attempt to receive data was not possible if the SC
was waiting for more room in the channel buffer. A BUG_ON() was added to detect
bugs. And in fact, it is possible.

The regression was added in commit 341a5783b ("BUG/MEDIUM: stconn: stop to
enable/disable reads from streams via si_update_rx").

This patch should fix the issue #2115. It must be backported if the commit
above is backported.
---

diff --git a/src/stconn.c b/src/stconn.c
index b1d02d95f9..95fe9c5e46 100644
--- a/src/stconn.c
+++ b/src/stconn.c
@@ -1194,7 +1194,7 @@ static int sc_conn_recv(struct stconn *sc)
 	/* If another call to sc_conn_recv() failed, and we subscribed to
 	 * recv events already, give up now.
 	 */
-	if (sc->wait_event.events & SUB_RETRY_RECV)
+	if ((sc->wait_event.events & SUB_RETRY_RECV) || sc_waiting_room(sc))
 		return 0;
 
 	/* maybe we were called immediately after an asynchronous shutr */
@@ -1220,7 +1220,6 @@ static int sc_conn_recv(struct stconn *sc)
 
 	/* prepare to detect if the mux needs more room */
 	sc_ep_clr(sc, SE_FL_WANT_ROOM);
-	BUG_ON(sc_waiting_room(sc));
 
 	if ((ic->flags & (CF_STREAMER | CF_STREAMER_FAST)) && !co_data(ic) &&
 	    global.tune.idle_timer &&