From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Graf Subject: [PATCH] sctp: verify length provided in heartbeat information parameter Date: Fri, 30 Nov 2012 12:16:27 +0000 Message-ID: <20121130121627.GG30697@casper.infradead.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, linux-sctp@vger.kernel.org To: davem@davemloft.net Return-path: Received: from casper.infradead.org ([85.118.1.10]:42195 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756394Ab2K3MQ2 (ORCPT ); Fri, 30 Nov 2012 07:16:28 -0500 Content-Disposition: inline Sender: netdev-owner@vger.kernel.org List-ID: If the variable parameter length provided in the mandatory heartbeat information parameter exceeds the calculated payload length the packet has been corrupted. Reply with a parameter length protocol violation message. Signed-off-by: Thomas Graf --- net/sctp/sm_statefuns.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c index b6adef8..e92079d 100644 --- a/net/sctp/sm_statefuns.c +++ b/net/sctp/sm_statefuns.c @@ -1055,6 +1055,7 @@ sctp_disposition_t sctp_sf_beat_8_3(struct net *net, void *arg, sctp_cmd_seq_t *commands) { + sctp_paramhdr_t *param_hdr; struct sctp_chunk *chunk = arg; struct sctp_chunk *reply; size_t paylen = 0; @@ -1072,12 +1073,17 @@ sctp_disposition_t sctp_sf_beat_8_3(struct net *net, * Information field copied from the received HEARTBEAT chunk. */ chunk->subh.hb_hdr = (sctp_heartbeathdr_t *) chunk->skb->data; + param_hdr = (sctp_paramhdr_t *) chunk->subh.hb_hdr; paylen = ntohs(chunk->chunk_hdr->length) - sizeof(sctp_chunkhdr_t); + + if (ntohs(param_hdr->length) > paylen) + return sctp_sf_violation_paramlen(net, ep, asoc, type, arg, + param_hdr, commands); + if (!pskb_pull(chunk->skb, paylen)) goto nomem; - reply = sctp_make_heartbeat_ack(asoc, chunk, - chunk->subh.hb_hdr, paylen); + reply = sctp_make_heartbeat_ack(asoc, chunk, param_hdr, paylen); if (!reply) goto nomem;