diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h
index 5c491a3bc27e4ddeaec70de31845cdf95a4d47ff..a499341472add5ee0230f94b62fc63ac59190aeb 100644
--- a/include/net/sctp/sm.h
+++ b/include/net/sctp/sm.h
@@ -380,6 +380,7 @@ sctp_vtag_verify(const struct sctp_chunk *chunk,
         if (ntohl(chunk->sctp_hdr->vtag) == asoc->c.my_vtag)
                 return 1;
 
+	chunk->transport->encap_port = SCTP_INPUT_CB(chunk->skb)->encap_port;
 	return 0;
 }
 
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index aa98e7e659ac3d00e7c6cf70360b68a79e7ea070..81464ae2b1378de9d7c11e8e7e94ae850eef627f 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1120,14 +1120,9 @@ static inline void sctp_outq_cork(struct sctp_outq *q)
  * sctp_input_cb is currently used on rx and sock rx queue
  */
 struct sctp_input_cb {
-	union {
-		struct inet_skb_parm	h4;
-#if IS_ENABLED(CONFIG_IPV6)
-		struct inet6_skb_parm	h6;
-#endif
-	} header;
 	struct sctp_chunk *chunk;
 	struct sctp_af *af;
+	__be16 encap_port;
 };
 #define SCTP_INPUT_CB(__skb)	((struct sctp_input_cb *)&((__skb)->cb[0]))
 
diff --git a/net/sctp/ipv6.c b/net/sctp/ipv6.c
index 8a58f42d6d1954996b8b8c1ac6925b57100e792b..a064bf252b170ccc027934de532fcb144f429b28 100644
--- a/net/sctp/ipv6.c
+++ b/net/sctp/ipv6.c
@@ -1053,6 +1053,7 @@ static struct inet_protosw sctpv6_stream_protosw = {
 
 static int sctp6_rcv(struct sk_buff *skb)
 {
+	memset(skb->cb, 0, sizeof(skb->cb));
 	return sctp_rcv(skb) ? -1 : 0;
 }
 
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index 89dfd313e1136b5b4876feb46a79da5af2f14655..f3de8c03a15e71888255ad75ed1e2f5784914935 100644
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -843,6 +843,9 @@ static int sctp_ctl_sock_init(struct net *net)
 
 static int sctp_udp_rcv(struct sock *sk, struct sk_buff *skb)
 {
+	memset(skb->cb, 0, sizeof(skb->cb));
+	SCTP_INPUT_CB(skb)->encap_port = udp_hdr(skb)->source;
+
 	skb_set_transport_header(skb, sizeof(struct udphdr));
 	sctp_rcv(skb);
 	return 0;
@@ -1139,9 +1142,15 @@ static struct inet_protosw sctp_stream_protosw = {
 	.flags      = SCTP_PROTOSW_FLAG
 };
 
+static int sctp4_rcv(struct sk_buff *skb)
+{
+	memset(skb->cb, 0, sizeof(skb->cb));
+	return sctp_rcv(skb);
+}
+
 /* Register with IP layer.  */
 static const struct net_protocol sctp_protocol = {
-	.handler     = sctp_rcv,
+	.handler     = sctp4_rcv,
 	.err_handler = sctp_v4_err,
 	.no_policy   = 1,
 	.netns_ok    = 1,
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 9a56ae2f3651567954e14ca91e7a5e4a151404f3..21d0ff1c6ab9d9a0f0475dda67f9ea32687798ee 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -2321,6 +2321,7 @@ int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
 	 * added as the primary transport.  The source address seems to
 	 * be a better choice than any of the embedded addresses.
 	 */
+	asoc->encap_port = SCTP_INPUT_CB(chunk->skb)->encap_port;
 	if (!sctp_assoc_add_peer(asoc, peer_addr, gfp, SCTP_ACTIVE))
 		goto nomem;
 
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index c669f8bd1eab2f629bd4bf26a041921d2dcabb44..8edab1533057fcfc99e783ad51b70bd0fb73a068 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -6268,6 +6268,8 @@ static struct sctp_packet *sctp_ootb_pkt_new(
 	if (!transport)
 		goto nomem;
 
+	transport->encap_port = SCTP_INPUT_CB(chunk->skb)->encap_port;
+
 	/* Cache a route for the transport with the chunk's destination as
 	 * the source address.
 	 */