sctp: fix src address selection if using secondary addresses

[cascardo/linux.git] / net / sctp / protocol.c

diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index fa80fe4..4345790 100644 (file)
--- a/net/sctp/protocol.c
+++ b/net/sctp/protocol.c
@@ -487,6 +487,8 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
         */
        rcu_read_lock();
        list_for_each_entry_rcu(laddr, &bp->address_list, list) {
+               struct net_device *odev;
+
                if (!laddr->valid)
                        continue;
                if (laddr->state != SCTP_ADDR_SRC ||
@@ -504,6 +506,14 @@ static void sctp_v4_get_dst(struct sctp_transport *t, union sctp_addr *saddr,
                if (IS_ERR(rt))
                        continue;
 
+               /* Ensure the src address belongs to the output
+                * interface.
+                */
+               odev = __ip_dev_find(sock_net(sk), laddr->a.v4.sin_addr.s_addr,
+                                    false);
+               if (!odev || odev->ifindex != fl4->flowi4_oif)
+                       continue;
+
                dst = &rt->dst;
                break;
        }