From: David Laight <David.Laight@ACULAB.COM>
Date: Wed, 19 Aug 2020 14:40:52 +0000 (+0000)
Subject: net: sctp: Fix negotiation of the number of data streams.
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=ab921f3cdbec01c68705a7ade8bec628d541fc2b;p=linux.git

net: sctp: Fix negotiation of the number of data streams.

The number of output and input streams was never being reduced, eg when
processing received INIT or INIT_ACK chunks.
The effect is that DATA chunks can be sent with invalid stream ids
and then discarded by the remote system.

Fixes: 2075e50caf5ea ("sctp: convert to genradix")
Signed-off-by: David Laight <david.laight@aculab.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index bda2536dd740f..6dc95dcc0ff4f 100644
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -88,12 +88,13 @@ static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
 	int ret;
 
 	if (outcnt <= stream->outcnt)
-		return 0;
+		goto out;
 
 	ret = genradix_prealloc(&stream->out, outcnt, gfp);
 	if (ret)
 		return ret;
 
+out:
 	stream->outcnt = outcnt;
 	return 0;
 }
@@ -104,12 +105,13 @@ static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
 	int ret;
 
 	if (incnt <= stream->incnt)
-		return 0;
+		goto out;
 
 	ret = genradix_prealloc(&stream->in, incnt, gfp);
 	if (ret)
 		return ret;
 
+out:
 	stream->incnt = incnt;
 	return 0;
 }