From: Christopher Faulet <cfaulet@haproxy.com>
Date: Tue, 28 Nov 2023 21:24:45 +0000 (+0100)
Subject: BUG/MEDIUM: mux-quic: Stop zero-copy FF during nego if input is not empty
X-Git-Tag: v2.9-dev12~36
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=61749d7cb78766464b4caa1545cc70528451661c;p=thirdparty%2Fhaproxy.git

BUG/MEDIUM: mux-quic: Stop zero-copy FF during nego if input is not empty

When the producer negociate with the QUIC mux to perform a zero-copy
fast-forward, data in the input buffer are first transferred in the H3
buffer. However, after the transfer, if the input buffer is not empty, the
data fast-forwarding must be stopped. In this case, qmux_nego_ff() must
return 0.

No backport needed.
---

diff --git a/src/mux_quic.c b/src/mux_quic.c
index c22668c834..36e5671a1e 100644
--- a/src/mux_quic.c
+++ b/src/mux_quic.c
@@ -2843,8 +2843,10 @@ static size_t qmux_nego_ff(struct stconn *sc, struct buffer *input, size_t count
 		b_sub(qcs->sd->iobuf.buf, qcs->sd->iobuf.offset);
 
 		/* Cannot forward more data, wait for room */
-		if (b_data(input))
+		if (b_data(input)) {
+			ret = 0;
 			goto end;
+		}
 	}
 	ret -= qcs->sd->iobuf.data;