[PATCH] bonding: suppress duplicate packets

	Originally submitted by Kenzo Iwami; his original description is:

The current bonding driver receives duplicate packets when broadcast/
multicast packets are sent by other devices or packets are flooded by the
switch. In this patch, new flags are added in priv_flags of net_device
structure to let the bonding driver discard duplicate packets in
dev.c:skb_bond().

	Modified by Jay Vosburgh to change a define name, update some
comments, rearrange the new skb_bond() for clarity, clear all bonding
priv_flags on slave release, and update the driver version.

Signed-off-by: Kenzo Iwami <k-iwami@cj.jp.nec.com>
Signed-off-by: Jay Vosburgh <fubar@us.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 25 insertions, 1 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 225e38ff57c..ef56c035d44 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1446,8 +1446,29 @@ static inline struct net_device *skb_bond(struct sk_buff *skb)
 {
 	struct net_device *dev = skb->dev;
 
-	if (dev->master)
+	if (dev->master) {
+		/*
+		 * On bonding slaves other than the currently active
+		 * slave, suppress duplicates except for 802.3ad
+		 * ETH_P_SLOW and alb non-mcast/bcast.
+		 */
+		if (dev->priv_flags & IFF_SLAVE_INACTIVE) {
+			if (dev->master->priv_flags & IFF_MASTER_ALB) {
+				if (skb->pkt_type != PACKET_BROADCAST &&
+				    skb->pkt_type != PACKET_MULTICAST)
+					goto keep;
+			}
+
+			if (dev->master->priv_flags & IFF_MASTER_8023AD &&
+			    skb->protocol == __constant_htons(ETH_P_SLOW))
+				goto keep;
+		
+			kfree_skb(skb);
+			return NULL;
+		}
+keep:
 		skb->dev = dev->master;
+	}
 
 	return dev;
 }
@@ -1591,6 +1612,9 @@ int netif_receive_skb(struct sk_buff *skb)
 
 	orig_dev = skb_bond(skb);
 
+	if (!orig_dev)
+		return NET_RX_DROP;
+
 	__get_cpu_var(netdev_rx_stat).total++;
 
 	skb->h.raw = skb->nh.raw = skb->data;