4 files changed, 27 insertions, 9 deletions
diff --git a/net/rds/connection.c b/net/rds/connection.c
index f2fcab182095..a3bc4b54d491 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -240,12 +240,23 @@ static struct rds_connection *__rds_conn_create(struct net *net,
 	if (loop_trans) {
 		rds_trans_put(loop_trans);
 		conn->c_loopback = 1;
-		if (is_outgoing && trans->t_prefer_loopback) {
-			/* "outgoing" connection - and the transport
-			 * says it wants the connection handled by the
-			 * loopback transport. This is what TCP does.
-			 */
-			trans = &rds_loop_transport;
+		if (trans->t_prefer_loopback) {
+			if (likely(is_outgoing)) {
+				/* "outgoing" connection to local address.
+				 * Protocol says it wants the connection
+				 * handled by the loopback transport.
+				 * This is what TCP does.
+				 */
+				trans = &rds_loop_transport;
+			} else {
+				/* No transport currently in use
+				 * should end up here, but if it
+				 * does, reset/destroy the connection.
+				 */
+				kmem_cache_free(rds_conn_slab, conn);
+				conn = ERR_PTR(-EOPNOTSUPP);
+				goto out;
+			}
 		}
 	}
 
diff --git a/net/rds/tcp.c b/net/rds/tcp.c
index 43db0eca911f..abf19c0e3ba0 100644
--- a/net/rds/tcp.c
+++ b/net/rds/tcp.c
@@ -313,8 +313,8 @@ out:
 }
 #endif
 
-static int rds_tcp_laddr_check(struct net *net, const struct in6_addr *addr,
-			       __u32 scope_id)
+int rds_tcp_laddr_check(struct net *net, const struct in6_addr *addr,
+			__u32 scope_id)
 {
 	struct net_device *dev = NULL;
 #if IS_ENABLED(CONFIG_IPV6)
diff --git a/net/rds/tcp.h b/net/rds/tcp.h
index bad9cf49d565..dc8d745d6857 100644
--- a/net/rds/tcp.h
+++ b/net/rds/tcp.h
@@ -59,7 +59,8 @@ u32 rds_tcp_snd_una(struct rds_tcp_connection *tc);
 u64 rds_tcp_map_seq(struct rds_tcp_connection *tc, u32 seq);
 extern struct rds_transport rds_tcp_transport;
 void rds_tcp_accept_work(struct sock *sk);
-
+int rds_tcp_laddr_check(struct net *net, const struct in6_addr *addr,
+			__u32 scope_id);
 /* tcp_connect.c */
 int rds_tcp_conn_path_connect(struct rds_conn_path *cp);
 void rds_tcp_conn_path_shutdown(struct rds_conn_path *conn);
diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c
index 101cf14215a0..09cadd556d1e 100644
--- a/net/rds/tcp_listen.c
+++ b/net/rds/tcp_listen.c
@@ -167,6 +167,12 @@ int rds_tcp_accept_one(struct socket *sock)
 	}
 #endif
 
+	if (!rds_tcp_laddr_check(sock_net(sock->sk), peer_addr, dev_if)) {
+		/* local address connection is only allowed via loopback */
+		ret = -EOPNOTSUPP;
+		goto out;
+	}
+
 	conn = rds_conn_create(sock_net(sock->sk),
 			       my_addr, peer_addr,
 			       &rds_tcp_transport, 0, GFP_KERNEL, dev_if);