netdev - [PATCH net-next 2/4] net: bridge: rearrange flood vs unicast receive paths

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:	Thu, 14 Jul 2016 06:10:00 +0300
From:	Nikolay Aleksandrov <nikolay@...ulusnetworks.com>
To:	netdev@...r.kernel.org
Cc:	roopa@...ulusnetworks.com, stephen@...workplumber.org,
	davem@...emloft.net, bridge@...ts.linux-foundation.org,
	Nikolay Aleksandrov <nikolay@...ulusnetworks.com>
Subject: [PATCH net-next 2/4] net: bridge: rearrange flood vs unicast receive paths

This patch removes one conditional from the unicast path by using the fact
that skb is NULL only when the packet is multicast or is local.

Signed-off-by: Nikolay Aleksandrov <nikolay@...ulusnetworks.com>
---
 net/bridge/br_input.c | 29 ++++++++++++++---------------
 1 file changed, 14 insertions(+), 15 deletions(-)

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 0b6d32619468..c20c5be6fc22 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -134,10 +134,10 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 	struct net_bridge_port *p = br_port_get_rcu(skb->dev);
 	const unsigned char *dest = eth_hdr(skb)->h_dest;
 	struct net_bridge_fdb_entry *dst = NULL;
+	bool mcast_hit = false, unicast = true;
 	struct net_bridge_mdb_entry *mdst;
 	struct net_bridge *br;
 	struct sk_buff *skb2;
-	bool unicast = true;
 	u16 vid = 0;
 
 	if (!p || p->state == BR_STATE_DISABLED)
@@ -177,30 +177,29 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb
 		if ((mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb)) &&
 		    br_multicast_querier_exists(br, eth_hdr(skb))) {
 			if ((mdst && mdst->mglist) ||
-			    br_multicast_is_router(br))
+			    br_multicast_is_router(br)) {
 				skb2 = skb;
-			br_multicast_forward(mdst, skb, skb2);
-			skb = NULL;
-			if (!skb2)
-				goto out;
+				br->dev->stats.multicast++;
+			}
+			mcast_hit = true;
 		} else {
 			skb2 = skb;
+			br->dev->stats.multicast++;
 		}
 		unicast = false;
-		br->dev->stats.multicast++;
 	} else if ((dst = __br_fdb_get(br, dest, vid)) && dst->is_local) {
-		skb2 = skb;
 		/* Do not forward the packet since it's local. */
-		skb = NULL;
+		return br_pass_frame_up(skb);
 	}
 
-	if (skb) {
-		if (dst) {
-			dst->used = jiffies;
-			br_forward(dst->dst, skb, skb2);
-		} else {
+	if (dst) {
+		dst->used = jiffies;
+		br_forward(dst->dst, skb, skb2);
+	} else {
+		if (!mcast_hit)
 			br_flood_forward(br, skb, skb2, unicast);
-		}
+		else
+			br_multicast_forward(mdst, skb, skb2);
 	}
 
 	if (skb2)
-- 
2.4.3