From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Fri, 5 Jun 2026 08:22:50 +0000 (+0200)
Subject: BUG/MINOR: mux_quic: do not interrupt recv on error/incomplete data
X-Git-Url: http://git.ipfire.org/gitweb/index.cgi?a=commitdiff_plain;h=refs%2Fremotes%2Fflx04%2Fquic-interop;p=thirdparty%2Fhaproxy.git

BUG/MINOR: mux_quic: do not interrupt recv on error/incomplete data

Prior to this patch, qcc_io_recv() stream decoding loop was interrupted
on the first decoding error or if incomplete data could not be parsed.

This patch adjusts this part so that loop is stopped only on a
connection level error. In case of a stream level error or on incomplete
data, decoding continues on the next QCS entry.

Without this patch, there is a risk that a QCS decode is not performed
as expected, with a possible client timeout firing. This is pretty
unlikely though. However this patch is still necessary to remove
completely this possibility.

This should be backported up to 3.2.
---

diff --git a/src/mux_quic.c b/src/mux_quic.c
index a6c4983f7..509e3aa7a 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -3319,6 +3319,7 @@ static int qcc_io_recv(struct qcc *qcc)
 			qcc_qmux_recv(qcc);
 	}
 
+ next_recv:
 	while (!LIST_ISEMPTY(&qcc->recv_list)) {
 		qcs = LIST_ELEM(qcc->recv_list.n, struct qcs *, el_recv);
 		/* No need to add an uni local stream in recv_list. */
@@ -3328,7 +3329,11 @@ static int qcc_io_recv(struct qcc *qcc)
 			ret = qcc_decode_qcs(qcc, qcs);
 			if (ret <= 0) {
 				LIST_DEL_INIT(&qcs->el_recv);
-				goto done;
+				/* Interrupt all receive if connection on error. */
+				if (qcc->flags & QC_CF_ERRL)
+					goto done;
+				/* Decode next entry if stream on error. */
+				goto next_recv;
 			}
 
 			total += ret;