From 3c6e5f2f5ef11bdba41e8158cc3c3e8ee6cfd198 Mon Sep 17 00:00:00 2001 From: Xin Long Date: Mon, 15 Jan 2018 17:01:19 +0800 Subject: [PATCH] sctp: reinit stream if stream outcnt has been change by sinit in sendmsg [ Upstream commit 625637bf4afa45204bd87e4218645182a919485a ] After introducing sctp_stream structure, sctp uses stream->outcnt as the out stream nums instead of c.sinit_num_ostreams. However when users use sinit in cmsg, it only updates c.sinit_num_ostreams in sctp_sendmsg. At that moment, stream->outcnt is still using previous value. If it's value is not updated, the sinit_num_ostreams of sinit could not really work. This patch is to fix it by updating stream->outcnt and reiniting stream if stream outcnt has been change by sinit in sendmsg. Fixes: a83863174a61 ("sctp: prepare asoc stream for stream reconf") Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/sctp/socket.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index 7d432266645c..1c08d86efe94 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1880,8 +1880,14 @@ static int sctp_sendmsg(struct sock *sk, struct msghdr *msg, size_t msg_len) */ if (sinit) { if (sinit->sinit_num_ostreams) { - asoc->c.sinit_num_ostreams = - sinit->sinit_num_ostreams; + __u16 outcnt = sinit->sinit_num_ostreams; + + asoc->c.sinit_num_ostreams = outcnt; + /* outcnt has been changed, so re-init stream */ + err = sctp_stream_init(&asoc->stream, outcnt, 0, + GFP_KERNEL); + if (err) + goto out_free; } if (sinit->sinit_max_instreams) { asoc->c.sinit_max_instreams =