4.9-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 d30fc5126efb0c33b7adf5966d3051db2c3d7721 ]
Now outstanding_bytes is only increased when appending chunks into one packet and sending it at 1st time, while decreased when it is about to move into retransmit queue. It means outstanding_bytes value is already decreased for all chunks in retransmit queue.
However sctp_prsctp_prune_sent is a common function to check the chunks in both transmitted and retransmit queue, it decrease outstanding_bytes when moving a chunk into abandoned queue from either of them.
It could cause outstanding_bytes underflow, as it also decreases it's value for the chunks in retransmit queue.
This patch fixes it by only updating outstanding_bytes for transmitted queue when pruning queues for prsctp prio policy, the same fix is also needed in sctp_check_transmitted.
Fixes: 8dbdf1f5b09c ("sctp: implement prsctp PRIO policy") Signed-off-by: Xin Long lucien.xin@gmail.com Acked-by: Marcelo Ricardo Leitner marcelo.leitner@gmail.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/sctp/outqueue.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
--- a/net/sctp/outqueue.c +++ b/net/sctp/outqueue.c @@ -364,7 +364,8 @@ static int sctp_prsctp_prune_sent(struct asoc->sent_cnt_removable--; asoc->abandoned_sent[SCTP_PR_INDEX(PRIO)]++;
- if (!chk->tsn_gap_acked) { + if (queue != &asoc->outqueue.retransmit && + !chk->tsn_gap_acked) { if (chk->transport) chk->transport->flight_size -= sctp_data_size(chk); @@ -1409,7 +1410,8 @@ static void sctp_check_transmitted(struc /* If this chunk has not been acked, stop * considering it as 'outstanding'. */ - if (!tchunk->tsn_gap_acked) { + if (transmitted_queue != &q->retransmit && + !tchunk->tsn_gap_acked) { if (tchunk->transport) tchunk->transport->flight_size -= sctp_data_size(tchunk);