[PATCH net] sctp: clear the new asoc's stream outcnt in sctp_stream_update

[Xin Long]

When processing a duplicate cookie-echo chunk, sctp moves the new
temp asoc's stream out/in into the old asoc, and later frees this
new temp asoc.

But now after this move, the new temp asoc's stream->outcnt is not
cleared while stream->out is set to NULL, which would cause a same
crash as the one fixed in Commit 79d0895140e9 ("sctp: fix error
path in sctp_stream_init") when freeing this asoc later.

This fix is to clear this outcnt in sctp_stream_update.

Fixes: f952be79cebd ("sctp: introduce struct sctp_stream_out_ext")
Reported-by: Jianwen Ji <j...@redhat.com>
Signed-off-by: Xin Long <lucien....@gmail.com>
---
 net/sctp/stream.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index f799043..f1f1d1b 100644
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -240,6 +240,8 @@ void sctp_stream_update(struct sctp_stream *stream, struct 
sctp_stream *new)
 
        new->out = NULL;
        new->in  = NULL;
+       new->outcnt = 0;
+       new->incnt  = 0;
 }
 
 static int sctp_send_reconf(struct sctp_association *asoc,
-- 
2.1.0