- Fix a bug in sctp_calc_rwnd() which resulted in wrong rwnd predictions.

- Fix a signedness problem that shows up in some 64 bit platforms (macos).

MFC after:	1 week

sys/netinet/sctp_indata.c

@@ -170,8 +170,8 @@ sctp_calc_rwnd(struct sctp_tcb *stcb, struct sctp_association *asoc)
  		 */
 		result = 1;
 	}
-	if (asoc->my_rwnd &&
-	    (asoc->my_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_receiver)) {
+	if (result &&
+	    (result < stcb->sctp_ep->sctp_ep.sctp_sws_receiver)) {
 		/* SWS engaged, tell peer none left */
 		result = 1;
 	}

sys/netinet/sctputil.c

@@ -4934,7 +4934,7 @@ sctp_sorecvmsg(struct socket *so,
 	int out_flags = 0, in_flags = 0;
 	int block_allowed = 1;
 	uint32_t freed_so_far = 0;
-	int copied_so_far = 0;
+	uint32_t copied_so_far = 0;
 	int in_eeor_mode = 0;
 	int no_rcv_needed = 0;
 	uint32_t rwnd_req = 0;