SCTP: Send ABORT chunk with correct tag in response to INIT ACK

When SCTP client received an INIT ACK chunk with missing mandatory
parameter such as "cookie parameter", it will send back a ABORT
with T-bit not set and verification tag is set to 0.
This is because before we accept this INIT ACK chunk, we do not know
the peer's tag.  This patch change to reflect vtag when responding to
INIT ACK with missing mandatory parameter.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>

diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 177528ed3e1b1d9f50ea2c9be844d5a5d0553187..385f1757158a3272c50ce20099563b5d78055e9e 100644 (file)
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -5176,7 +5176,22 @@ static struct sctp_packet *sctp_ootb_pkt_new(const struct sctp_association *asoc
         * association exists, otherwise, use the peer's vtag.
         */
        if (asoc) {
-               vtag = asoc->peer.i.init_tag;
+               /* Special case the INIT-ACK as there is no peer's vtag
+                * yet.
+                */
+               switch(chunk->chunk_hdr->type) {
+               case SCTP_CID_INIT_ACK:
+               {
+                       sctp_initack_chunk_t *initack;
+
+                       initack = (sctp_initack_chunk_t *)chunk->chunk_hdr;
+                       vtag = ntohl(initack->init_hdr.init_tag);
+                       break;
+               }
+               default:
+                       vtag = asoc->peer.i.init_tag;
+                       break;
+               }
        } else {
                /* Special case the INIT and stale COOKIE_ECHO as there is no
                 * vtag yet.