diff --git a/sys/netinet/sctp_pcb.h b/sys/netinet/sctp_pcb.h
index 1dc03a25cac..f037e847297 100644
--- a/sys/netinet/sctp_pcb.h
+++ b/sys/netinet/sctp_pcb.h
@@ -320,7 +320,7 @@ struct sctp_pcb {
 
 	uint32_t def_cookie_life;
 	/* defaults to 0 */
-	int auto_close_time;
+	uint32_t auto_close_time;
 	uint32_t initial_sequence_debug;
 	uint32_t adaptation_layer_indicator;
 	uint8_t adaptation_layer_indicator_provided;
diff --git a/sys/netinet/sctp_structs.h b/sys/netinet/sctp_structs.h
index f7e2a2c4173..dd18fa44bf1 100644
--- a/sys/netinet/sctp_structs.h
+++ b/sys/netinet/sctp_structs.h
@@ -275,7 +275,7 @@ struct sctp_nets {
 	int lastsa;
 	int lastsv;
 	uint64_t rtt;		/* last measured rtt value in us */
-	unsigned int RTO;
+	uint32_t RTO;
 
 	/* This is used for SHUTDOWN/SHUTDOWN-ACK/SEND or INIT timers */
 	struct sctp_timer rxt_timer;
@@ -1071,7 +1071,7 @@ struct sctp_association {
 	unsigned int max_inbound_streams;
 
 	/* the cookie life I award for any cookie, in seconds */
-	unsigned int cookie_life;
+	uint32_t cookie_life;
 	/* time to delay acks for */
 	unsigned int delayed_ack;
 	unsigned int old_delayed_ack;
@@ -1080,10 +1080,10 @@ struct sctp_association {
 
 	unsigned int numduptsns;
 	int dup_tsns[SCTP_MAX_DUP_TSNS];
-	unsigned int initial_init_rto_max;	/* initial RTO for INIT's */
-	unsigned int initial_rto;	/* initial send RTO */
-	unsigned int minrto;	/* per assoc RTO-MIN */
-	unsigned int maxrto;	/* per assoc RTO-MAX */
+	uint32_t initial_init_rto_max;	/* initial RTO for INIT's */
+	uint32_t initial_rto;	/* initial send RTO */
+	uint32_t minrto;	/* per assoc RTO-MIN */
+	uint32_t maxrto;	/* per assoc RTO-MAX */
 
 	/* authentication fields */
 	sctp_auth_chklist_t *local_auth_chunks;