4.14-stable review patch. If anyone has any objections, please let me know.
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From: Xin Long lucien.xin@gmail.com
[ 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 lucien.xin@gmail.com Acked-by: Neil Horman nhorman@tuxdriver.com Acked-by: Marcelo Ricardo Leitner marcelo.leitner@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sctp/socket.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
--- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -1880,8 +1880,14 @@ static int sctp_sendmsg(struct sock *sk, */ 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 =