From 06a31e2b918dd992dd104e082ec8a33d6235c7b3 Mon Sep 17 00:00:00 2001 From: Thomas Graf Date: Fri, 30 Nov 2012 02:16:27 +0000 Subject: [PATCH] sctp: verify length provided in heartbeat information parameter 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 Acked-by: Neil Horman Signed-off-by: David S. Miller --- 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 b6adef8a1e93..e92079d27eae 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; -- 2.30.2