[SCTP] Fix a couple of issues with the call to sctp_ssnmap_new() in

sctp_process_init().

The argument passed as inbound streams to sctp_ssnmap_new() is
incorrect. Also allocating a ssnmap everytime a INIT is received is
vulnerable to DoS attacks. So delay the creation of an ssnmap if we
are processing a temporary association. 

net/sctp/sm_make_chunk.c

@@ -1813,11 +1813,14 @@ int sctp_process_init(struct sctp_association *asoc, sctp_cid_t cid,
 	 * stream sequence number shall be set to 0.
 	 */
 
-	/* Allocate storage for the negotiated streams. */
-	asoc->ssnmap = sctp_ssnmap_new(asoc->peer.i.num_outbound_streams,
-				       asoc->c.sinit_num_ostreams, gfp);
-	if (!asoc->ssnmap)
-		goto nomem_ssnmap;
+	/* Allocate storage for the negotiated streams if it is not a temporary 	 * association.
+	 */
+	if (!asoc->temp) {
+		asoc->ssnmap = sctp_ssnmap_new(asoc->c.sinit_max_instreams,
+					       asoc->c.sinit_num_ostreams, gfp);
+		if (!asoc->ssnmap)
+			goto nomem_ssnmap;
+	}
 
 	/* ADDIP Section 4.1 ASCONF Chunk Procedures
 	 *

net/sctp/socket.c

@@ -1435,7 +1435,7 @@ static int sctp_setsockopt_initmsg(struct sock *sk, char *optval, int optlen)
 }
 
 /*
- * 7.1.14 Set default send parameters (SET_DEFAULT_SEND_PARAM)
+ * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
  *
  *   Applications that wish to use the sendto() system call may wish to
  *   specify a default set of parameters that would normally be supplied
@@ -2072,9 +2072,8 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk)
 		return -ESOCKTNOSUPPORT;
 	}
 
-	/* FIXME:  The next draft (04) of the SCTP Sockets Extensions
-	 * should include a socket option for manipulating these
-	 * message parameters (and a few others).
+	/* Initialize default send parameters. These parameters can be
+	 * modified with the SCTP_DEFAULT_SEND_PARAM socket option.
 	 */
 	sp->default_stream = 0;
 	sp->default_ppid = 0;
@@ -2093,7 +2092,6 @@ SCTP_STATIC int sctp_init_sock(struct sock *sk)
 
 	/* Initialize default RTO related parameters.  These parameters can
 	 * be modified for with the SCTP_RTOINFO socket option.
-	 * FIXME: These are not used yet.
 	 */
 	sp->rtoinfo.srto_initial = (sctp_rto_initial / HZ) * 1000;
 	sp->rtoinfo.srto_max     = (sctp_rto_max / HZ) * 1000;
@@ -2776,7 +2774,7 @@ static int sctp_getsockopt_primary_addr(struct sock *sk, int len,
 
 /*
  *
- * 7.1.14 Set default send parameters (SET_DEFAULT_SEND_PARAM)
+ * 7.1.14 Set default send parameters (SCTP_DEFAULT_SEND_PARAM)
  *
  *   Applications that wish to use the sendto() system call may wish to
  *   specify a default set of parameters that would normally be supplied