mac80211: fix miscounting of ttl-dropped frames

[ Upstream commit a0dc02039a2ee54fb4ae400e0b755ed30e73e58c ] In ieee80211_rx_h_mesh_fwding, we increment the 'dropped_frames_ttl' counter when we decrement the ttl to zero. For unicast frames destined for other hosts, we stop processing the frame at that point. For multicast frames, we do not rebroadcast it in this case, but we do pass the frame up the stack to process it on this STA. That doesn't match the usual definition of "dropped," so don't count those as such. With this change, something like `ping6 -i0.2 ff02::1%mesh0` from a peer in a ttl=1 network no longer increments the counter rapidly. Signed-off-by: Bob Copeland <[email protected]> Signed-off-by: Johannes Berg <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
akeromi · Mar 5, 2019 · a2887f6 · a2887f6
1 parent bbc300c
commit a2887f6
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
@@ -2678,7 +2678,9 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
 	skb_set_queue_mapping(skb, q);
 
 	if (!--mesh_hdr->ttl) {
-		IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
+		if (!is_multicast_ether_addr(hdr->addr1))
+			IEEE80211_IFSTA_MESH_CTR_INC(ifmsh,
+						     dropped_frames_ttl);
 		goto out;
 	}