mppath = mpp_path_lookup(skb->data, sdata);
 
                /*
-                * Do not use address extension, if it is a packet from
-                * the same interface and the destination is not being
-                * proxied by any other mest point.
+                * Use address extension if it is a packet from
+                * another interface or if we know the destination
+                * is being proxied by a portal (i.e. portal address
+                * differs from proxied address)
                 */
                if (compare_ether_addr(sdata->vif.addr,
                                       skb->data + ETH_ALEN) == 0 &&
-                   (!mppath || !compare_ether_addr(mppath->mpp, skb->data))) {
+                   !(mppath && compare_ether_addr(mppath->mpp, skb->data))) {
                        hdrlen = ieee80211_fill_mesh_addresses(&hdr, &fc,
                                        skb->data, skb->data + ETH_ALEN);
                        meshhdrlen = ieee80211_new_mesh_header(&mesh_hdr,
                                        sdata, NULL, NULL);
                } else {
-                       /* packet from other interface */
                        int is_mesh_mcast = 1;
                        const u8 *mesh_da;