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@xxxxxxxxxx> --- net/sctp/stream.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) This needs backporting to 5.1 and all later kernels. Changes since v1: - Fix 'Fixes' tag. - Improve description. diff --git a/net/sctp/stream.c b/net/sctp/stream.c index bda2536dd740..6dc95dcc0ff4 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; } -- 2.25.1 - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)