mac80211: mesh STAs only process mesh beacons

Before, a mesh STA would execute some code on behalf of AP or IBSS
beacons. Since the mesh stack currently does not consider anything but
other mesh STAs interesting, limit processing to just these and save a
little overhead.
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mesh.c

@@ -703,8 +703,10 @@ static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
 			       &elems);
 
-	/* ignore beacons from secure mesh peers if our security is off */
-	if (elems.rsn_len && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE)
+	/* ignore non-mesh or secure / unsecure mismatch */
+	if ((!elems.mesh_id || !elems.mesh_config) ||
+	    (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
+	    (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
 		return;
 
 	if (elems.ds_params && elems.ds_params_len == 1)
@@ -717,8 +719,7 @@ static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
 		return;
 
-	if (elems.mesh_id && elems.mesh_config &&
-	    mesh_matches_local(sdata, &elems))
+	if (mesh_matches_local(sdata, &elems))
 		mesh_neighbour_update(sdata, mgmt->sa, &elems);
 
 	if (ifmsh->sync_ops)