[SCTP]: Verify some mandatory parameters.

Verify init_tag and a_rwnd mandatory parameters in INIT and
INIT-ACK chunks.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 3 insertions, 20 deletions

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index ea0f8fac3f01..0b1ddb1005ac 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1775,7 +1775,9 @@ int sctp_verify_init(const struct sctp_association *asoc,
 
         /* Verify stream values are non-zero. */
         if ((0 == peer_init->init_hdr.num_outbound_streams) ||
-            (0 == peer_init->init_hdr.num_inbound_streams)) {
+            (0 == peer_init->init_hdr.num_inbound_streams) ||
+            (0 == peer_init->init_hdr.init_tag) ||
+            (SCTP_DEFAULT_MINWINDOW > ntohl(peer_init->init_hdr.a_rwnd))) {
 
                 sctp_process_inv_mandatory(asoc, chunk, errp);
                 return 0;
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index aa51d190bfb2..2c165dc9fb71 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -440,7 +440,6 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep,
 {
         struct sctp_chunk *chunk = arg;
         sctp_init_chunk_t *initchunk;
-        __u32 init_tag;
         struct sctp_chunk *err_chunk;
         struct sctp_packet *packet;
         sctp_error_t error;
@@ -462,24 +461,6 @@ sctp_disposition_t sctp_sf_do_5_1C_ack(const struct sctp_endpoint *ep,
         /* Grab the INIT header.  */
         chunk->subh.init_hdr = (sctp_inithdr_t *) chunk->skb->data;
 
-        init_tag = ntohl(chunk->subh.init_hdr->init_tag);
-
-        /* Verification Tag: 3.3.3
-         *   If the value of the Initiate Tag in a received INIT ACK
-         *   chunk is found to be 0, the receiver MUST treat it as an
-         *   error and close the association by transmitting an ABORT.
-         */
-        if (!init_tag) {
-                struct sctp_chunk *reply = sctp_make_abort(asoc, chunk, 0);
-                if (!reply)
-                        goto nomem;
-
-                sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(reply));
-                return sctp_stop_t1_and_abort(commands, SCTP_ERROR_INV_PARAM,
-                                              ECONNREFUSED, asoc,
-                                              chunk->transport);
-        }
-
         /* Verify the INIT chunk before processing it. */
         err_chunk = NULL;
         if (!sctp_verify_init(asoc, chunk->chunk_hdr->type,