[PATCH v2 2/4] sctp: fix association hangs due to reneging packets below the cumulative TSN ACK point
From: Lee A. Roberts <hidden>
Date: 2013-02-27 18:53:46
Subsystem:
networking [general], sctp protocol, the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Marcelo Ricardo Leitner, Xin Long, Linus Torvalds
From: "Lee A. Roberts" <redacted> Resolve SCTP association hangs observed during SCTP stress testing. Observable symptoms include communications hangs with data being held in the association reassembly and/or lobby (ordering) queues. Close examination of reassembly queue shows missing packets. In sctp_ulpq_renege_list(), do not renege packets below the cumulative TSN ACK point. Signed-off-by: Lee A. Roberts <redacted> --- net/sctp/ulpqueue.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c
index ada1746..63afddc 100644
--- a/net/sctp/ulpqueue.c
+++ b/net/sctp/ulpqueue.c@@ -969,11 +969,16 @@ static __u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq, tsnmap = &ulpq->asoc->peer.tsn_map; - while ((skb = __skb_dequeue_tail(list)) != NULL) { - freed += skb_headlen(skb); + while ((skb = skb_peek_tail(list)) != NULL) { event = sctp_skb2event(skb); tsn = event->tsn; + /* Don't renege below the Cumulative TSN ACK Point. */ + if (TSN_lte(tsn, sctp_tsnmap_get_ctsn(tsnmap))) + break; + + __skb_unlink(skb, list); + freed += skb_headlen(skb); sctp_ulpevent_free(event); sctp_tsnmap_renege(tsnmap, tsn); if (freed >= needed)
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1.7.9.5