bonding: don't increase rx_dropped after processing LACPDUs

Since commit 3aba891d, bonding processes LACP frames (802.3ad
mode) with bond_handle_frame(). Currently a copy of the skb is
made and the original is left to be processed by other
rx_handlers and the rest of the network stack by returning
RX_HANDLER_ANOTHER.  As there is no protocol handler for
PKT_TYPE_LACPDU, the frame is dropped and dev->rx_dropped
increased.

Fix this by making bond_handle_frame() return RX_HANDLER_CONSUMED
if bonding has processed the LACP frame.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 793b001..3463b46 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -2173,9 +2173,10 @@
  * received frames (loopback). Since only the payload is given to this
  * function, it check for loopback.
  */
-static void bond_3ad_rx_indication(struct lacpdu *lacpdu, struct slave *slave, u16 length)
+static int bond_3ad_rx_indication(struct lacpdu *lacpdu, struct slave *slave, u16 length)
 {
 	struct port *port;
+	int ret = RX_HANDLER_ANOTHER;
 
 	if (length >= sizeof(struct lacpdu)) {
 
@@ -2184,11 +2185,12 @@
 		if (!port->slave) {
 			pr_warning("%s: Warning: port of slave %s is uninitialized\n",
 				   slave->dev->name, slave->dev->master->name);
-			return;
+			return ret;
 		}
 
 		switch (lacpdu->subtype) {
 		case AD_TYPE_LACPDU:
+			ret = RX_HANDLER_CONSUMED;
 			pr_debug("Received LACPDU on port %d\n",
 				 port->actor_port_number);
 			/* Protect against concurrent state machines */
@@ -2198,6 +2200,7 @@
 			break;
 
 		case AD_TYPE_MARKER:
+			ret = RX_HANDLER_CONSUMED;
 			// No need to convert fields to Little Endian since we don't use the marker's fields.
 
 			switch (((struct bond_marker *)lacpdu)->tlv_type) {
@@ -2219,6 +2222,7 @@
 			}
 		}
 	}
+	return ret;
 }
 
 /**
@@ -2456,18 +2460,20 @@
 	return NETDEV_TX_OK;
 }
 
-void bond_3ad_lacpdu_recv(struct sk_buff *skb, struct bonding *bond,
+int bond_3ad_lacpdu_recv(struct sk_buff *skb, struct bonding *bond,
 			  struct slave *slave)
 {
+	int ret = RX_HANDLER_ANOTHER;
 	if (skb->protocol != PKT_TYPE_LACPDU)
-		return;
+		return ret;
 
 	if (!pskb_may_pull(skb, sizeof(struct lacpdu)))
-		return;
+		return ret;
 
 	read_lock(&bond->lock);
-	bond_3ad_rx_indication((struct lacpdu *) skb->data, slave, skb->len);
+	ret = bond_3ad_rx_indication((struct lacpdu *) skb->data, slave, skb->len);
 	read_unlock(&bond->lock);
+	return ret;
 }
 
 /*