Merge branch 'br-next'

Nikolay Aleksandrov says:

====================
net: bridge: add per-port unknown multicast flood control

The first patch prepares the forwarding path by having the exact packet
type passed down so we can later filter based on it and the per-port
unknown mcast flood flag introduced in the second patch. It is similar to
how the per-port unknown unicast flood flag works.
Nice side-effects of patch 01 are the slight reduction of tests in the
fast-path and a few minor checkpatch fixes.

v3: don't change br_auto_mask as that will change user-visible behaviour
v2: make pkt_type an enum as per Stephen's comment
====================

Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 25 insertions, 15 deletions

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 3132cfc80e9d..8a4368461fb0 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -131,11 +131,12 @@ static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br,
 /* note: already called with rcu_read_lock */
 int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
-	bool local_rcv = false, mcast_hit = false, unicast = true;
 	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
 	const unsigned char *dest = eth_hdr(skb)->h_dest;
+	enum br_pkt_type pkt_type = BR_PKT_UNICAST;
 	struct net_bridge_fdb_entry *dst = NULL;
 	struct net_bridge_mdb_entry *mdst;
+	bool local_rcv, mcast_hit = false;
 	struct net_bridge *br;
 	u16 vid = 0;
 
@@ -152,24 +153,29 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 	if (p->flags & BR_LEARNING)
 		br_fdb_update(br, p, eth_hdr(skb)->h_source, vid, false);
 
-	if (!is_broadcast_ether_addr(dest) && is_multicast_ether_addr(dest) &&
-	    br_multicast_rcv(br, p, skb, vid))
-		goto drop;
+	local_rcv = !!(br->dev->flags & IFF_PROMISC);
+	if (is_multicast_ether_addr(dest)) {
+		/* by definition the broadcast is also a multicast address */
+		if (is_broadcast_ether_addr(dest)) {
+			pkt_type = BR_PKT_BROADCAST;
+			local_rcv = true;
+		} else {
+			pkt_type = BR_PKT_MULTICAST;
+			if (br_multicast_rcv(br, p, skb, vid))
+				goto drop;
+		}
+	}
 
 	if (p->state == BR_STATE_LEARNING)
 		goto drop;
 
 	BR_INPUT_SKB_CB(skb)->brdev = br->dev;
 
-	local_rcv = !!(br->dev->flags & IFF_PROMISC);
-
 	if (IS_ENABLED(CONFIG_INET) && skb->protocol == htons(ETH_P_ARP))
 		br_do_proxy_arp(skb, br, vid, p);
 
-	if (is_broadcast_ether_addr(dest)) {
-		local_rcv = true;
-		unicast = false;
-	} else if (is_multicast_ether_addr(dest)) {
+	switch (pkt_type) {
+	case BR_PKT_MULTICAST:
 		mdst = br_mdb_get(br, skb, vid);
 		if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
 		    br_multicast_querier_exists(br, eth_hdr(skb))) {
@@ -183,18 +189,22 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 			local_rcv = true;
 			br->dev->stats.multicast++;
 		}
-		unicast = false;
-	} else if ((dst = __br_fdb_get(br, dest, vid)) && dst->is_local) {
-		/* Do not forward the packet since it's local. */
-		return br_pass_frame_up(skb);
+		break;
+	case BR_PKT_UNICAST:
+		dst = __br_fdb_get(br, dest, vid);
+	default:
+		break;
 	}
 
 	if (dst) {
+		if (dst->is_local)
+			return br_pass_frame_up(skb);
+
 		dst->used = jiffies;
 		br_forward(dst->dst, skb, local_rcv, false);
 	} else {
 		if (!mcast_hit)
-			br_flood(br, skb, unicast, local_rcv, false);
+			br_flood(br, skb, pkt_type, local_rcv, false);
 		else
 			br_multicast_flood(mdst, skb, local_rcv, false);
 	}