diff options
| -rw-r--r-- | net/sctp/input.c | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/net/sctp/input.c b/net/sctp/input.c index ca6b022..d354a23 100644 --- a/net/sctp/input.c +++ b/net/sctp/input.c @@ -430,6 +430,9 @@ struct sock *sctp_err_lookup(int family, struct sk_buff *skb, struct sock *sk = NULL; struct sctp_association *asoc; struct sctp_transport *transport = NULL; + struct sctp_init_chunk *chunkhdr; + __u32 vtag = ntohl(sctphdr->vtag); + int len = skb->len - ((void *)sctphdr - (void *)skb->data); *app = NULL; *tpp = NULL; @@ -451,8 +454,28 @@ struct sock *sctp_err_lookup(int family, struct sk_buff *skb, sk = asoc->base.sk; - if (ntohl(sctphdr->vtag) != asoc->c.peer_vtag) { - ICMP_INC_STATS_BH(ICMP_MIB_INERRORS); + /* RFC 4960, Appendix C. ICMP Handling + * + * ICMP6) An implementation MUST validate that the Verification Tag + * contained in the ICMP message matches the Verification Tag of + * the peer. If the Verification Tag is not 0 and does NOT + * match, discard the ICMP message. If it is 0 and the ICMP + * message contains enough bytes to verify that the chunk type is + * an INIT chunk and that the Initiate Tag matches the tag of the + * peer, continue with ICMP7. If the ICMP message is too short + * or the chunk type or the Initiate Tag does not match, silently + * discard the packet. + */ + if (vtag == 0) { + chunkhdr = (struct sctp_init_chunk *)((void *)sctphdr + + sizeof(struct sctphdr)); + if (len < sizeof(struct sctphdr) + sizeof(sctp_chunkhdr_t) + + sizeof(__be32) || + chunkhdr->chunk_hdr.type != SCTP_CID_INIT || + ntohl(chunkhdr->init_hdr.init_tag) != asoc->c.my_vtag) { + goto out; + } + } else if (vtag != asoc->c.peer_vtag) { goto out; } |