net: sctp: sctp_endpoint_free: zero out secret key data

On sctp_endpoint_destroy, previously used sensitive keying material
should be zeroed out before the memory is returned, as we already do
with e.g. auth keys when released.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/sctp/endpointola.c

@@ -249,6 +249,8 @@ void sctp_endpoint_free(struct sctp_endpoint *ep)
 /* Final destructor for endpoint.  */
 static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
 {
+	int i;
+
 	SCTP_ASSERT(ep->base.dead, "Endpoint is not dead", return);
 
 	/* Free up the HMAC transform. */
@@ -271,6 +273,9 @@ static void sctp_endpoint_destroy(struct sctp_endpoint *ep)
 	sctp_inq_free(&ep->base.inqueue);
 	sctp_bind_addr_free(&ep->base.bind_addr);
 
+	for (i = 0; i < SCTP_HOW_MANY_SECRETS; ++i)
+		memset(&ep->secret_key[i], 0, SCTP_SECRET_SIZE);
+
 	/* Remove and free the port */
 	if (sctp_sk(ep->base.sk)->bind_hash)
 		sctp_put_port(ep->base.sk);