Messages in this thread | | | Date | Thu, 21 Nov 2013 17:14:01 -0500 | From | Vlad Yasevich <> | Subject | Re: [PATCH] net: sctp: find the correct highest_new_tsn in sack |
| |
On 11/21/2013 04:56 PM, Chang Xiangzhong wrote: > Function sctp_check_transmitted(transport t, ...) would iterate all of > transport->transmitted queue and looking for the highest __newly__ acked tsn. > The original algorithm would depend on the order of the assoc->transport_list > (in function sctp_outq_sack line 1215 - 1226). The result might not be the > expected due to the order of the tranport_list. > > Solution: checking if the exising is smaller than the new one before assigning > > Signed-off-by: Chang Xiangzhong <changxiangzhong@gmail.com>
Good find. This has been around for since day 1. It doesn't so much depend on the order of the transport list, but on the order the transports been used. I agree it is a problem if chunks have been distributed across multiple transports and a singe SACK acking them all.
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
-vlad
> --- > net/sctp/outqueue.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c > index ef9e2bb..1b494fa 100644 > --- a/net/sctp/outqueue.c > +++ b/net/sctp/outqueue.c > @@ -1397,7 +1397,8 @@ static void sctp_check_transmitted(struct sctp_outq *q, > */ > if (!tchunk->tsn_gap_acked) { > tchunk->tsn_gap_acked = 1; > - *highest_new_tsn_in_sack = tsn; > + if (TSN_lt(*highest_new_tsn_in_sack, tsn)) > + *highest_new_tsn_in_sack = tsn; > bytes_acked += sctp_data_size(tchunk); > if (!tchunk->transport) > migrate_bytes += sctp_data_size(tchunk); >
| |