[VLAN]: Make sure bonding packet drop checks get done in hwaccel RX path.

Since __vlan_hwaccel_rx() is essentially bypassing the
netif_receive_skb() call that would have occurred if we did the VLAN
decapsulation in software, we are missing the skb_bond() call and the
assosciated checks it does.

Export those checks via an inline function, skb_bond_should_drop(),
and use this in __vlan_hwaccel_rx().
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/if_vlan.h

@@ -155,6 +155,11 @@ static inline int __vlan_hwaccel_rx(struct sk_buff *skb,
 {
 	struct net_device_stats *stats;
 
+	if (skb_bond_should_drop(skb)) {
+		dev_kfree_skb_any(skb);
+		return NET_RX_DROP;
+	}
+
 	skb->dev = grp->vlan_devices[vlan_tag & VLAN_VID_MASK];
 	if (skb->dev == NULL) {
 		dev_kfree_skb_any(skb);

include/linux/netdevice.h

@@ -1012,6 +1012,30 @@ static inline int netif_needs_gso(struct net_device *dev, struct sk_buff *skb)
 		unlikely(skb->ip_summed != CHECKSUM_HW));
 }
 
+/* On bonding slaves other than the currently active slave, suppress
+ * duplicates except for 802.3ad ETH_P_SLOW and alb non-mcast/bcast.
+ */
+static inline int skb_bond_should_drop(struct sk_buff *skb)
+{
+	struct net_device *dev = skb->dev;
+	struct net_device *master = dev->master;
+
+	if (master &&
+	    (dev->priv_flags & IFF_SLAVE_INACTIVE)) {
+		if (master->priv_flags & IFF_MASTER_ALB) {
+			if (skb->pkt_type != PACKET_BROADCAST &&
+			    skb->pkt_type != PACKET_MULTICAST)
+				return 0;
+		}
+		if (master->priv_flags & IFF_MASTER_8023AD &&
+		    skb->protocol == __constant_htons(ETH_P_SLOW))
+			return 0;
+
+		return 1;
+	}
+	return 0;
+}
+
 #endif /* __KERNEL__ */
 
 #endif	/* _LINUX_DEV_H */

net/core/dev.c

@@ -1619,26 +1619,10 @@ static inline struct net_device *skb_bond(struct sk_buff *skb)
 	struct net_device *dev = skb->dev;
 
 	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;
-		
+		if (skb_bond_should_drop(skb)) {
 			kfree_skb(skb);
 			return NULL;
 		}
-keep:
 		skb->dev = dev->master;
 	}