diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index 910926906a3a..73bdeb2b6c62 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -2570,6 +2570,12 @@ sctp_disposition_t sctp_sf_do_9_2_shutdown(const struct sctp_endpoint *ep, chunk->subh.shutdown_hdr = sdh; ctsn = ntohl(sdh->cum_tsn_ack); + if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { + SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); + SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); + return SCTP_DISPOSITION_DISCARD; + } + /* If Cumulative TSN Ack beyond the max tsn currently * send, terminating the association and respond to the * sender with an ABORT. @@ -2633,6 +2639,7 @@ sctp_disposition_t sctp_sf_do_9_2_shut_ctsn(const struct sctp_endpoint *ep, { struct sctp_chunk *chunk = arg; sctp_shutdownhdr_t *sdh; + __u32 ctsn; if (!sctp_vtag_verify(chunk, asoc)) return sctp_sf_pdiscard(ep, asoc, type, arg, commands); @@ -2644,12 +2651,19 @@ sctp_disposition_t sctp_sf_do_9_2_shut_ctsn(const struct sctp_endpoint *ep, commands); sdh = (sctp_shutdownhdr_t *)chunk->skb->data; + ctsn = ntohl(sdh->cum_tsn_ack); + + if (TSN_lt(ctsn, asoc->ctsn_ack_point)) { + SCTP_DEBUG_PRINTK("ctsn %x\n", ctsn); + SCTP_DEBUG_PRINTK("ctsn_ack_point %x\n", asoc->ctsn_ack_point); + return SCTP_DISPOSITION_DISCARD; + } /* If Cumulative TSN Ack beyond the max tsn currently * send, terminating the association and respond to the * sender with an ABORT. */ - if (!TSN_lt(ntohl(sdh->cum_tsn_ack), asoc->next_tsn)) + if (!TSN_lt(ctsn, asoc->next_tsn)) return sctp_sf_violation_ctsn(ep, asoc, type, arg, commands); /* verify, by checking the Cumulative TSN Ack field of the