net: neigh: use kfree_skb_reason() in neigh_resolve_output() and neigh_connected_output()

Replace kfree_skb() used in neigh_resolve_output() and
neigh_connected_output() with kfree_skb_reason().

Following new skb drop reason is added:
/* failed to fill the device hard header */
SKB_DROP_REASON_NEIGH_HH_FILLFAIL

Signed-off-by: Qiu Yutan <[email protected]>
Signed-off-by: Jiang Kun <[email protected]>
Reviewed-by: Kuniyuki Iwashima <[email protected]>
Reviewed-by: Xu Xin <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: Qiu Yutan

include/net/dropreason-core.h

@@ -62,6 +62,7 @@
 	FN(NEIGH_FAILED)		\
 	FN(NEIGH_QUEUEFULL)		\
 	FN(NEIGH_DEAD)			\
+	FN(NEIGH_HH_FILLFAIL)		\
 	FN(TC_EGRESS)			\
 	FN(SECURITY_HOOK)		\
 	FN(QDISC_DROP)			\
@@ -348,6 +349,8 @@ enum skb_drop_reason {
 	SKB_DROP_REASON_NEIGH_QUEUEFULL,
 	/** @SKB_DROP_REASON_NEIGH_DEAD: neigh entry is dead */
 	SKB_DROP_REASON_NEIGH_DEAD,
+	/** @SKB_DROP_REASON_NEIGH_HH_FILLFAIL: failed to fill the device hard header */
+	SKB_DROP_REASON_NEIGH_HH_FILLFAIL,
 	/** @SKB_DROP_REASON_TC_EGRESS: dropped in TC egress HOOK */
 	SKB_DROP_REASON_TC_EGRESS,
 	/** @SKB_DROP_REASON_SECURITY_HOOK: dropped due to security HOOK */

net/core/neighbour.c

@@ -1517,7 +1517,7 @@ int neigh_resolve_output(struct neighbour *neigh, struct sk_buff *skb)
 	return rc;
 out_kfree_skb:
 	rc = -EINVAL;
-	kfree_skb(skb);
+	kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_HH_FILLFAIL);
 	goto out;
 }
 EXPORT_SYMBOL(neigh_resolve_output);
@@ -1541,7 +1541,7 @@ int neigh_connected_output(struct neighbour *neigh, struct sk_buff *skb)
 		err = dev_queue_xmit(skb);
 	else {
 		err = -EINVAL;
-		kfree_skb(skb);
+		kfree_skb_reason(skb, SKB_DROP_REASON_NEIGH_HH_FILLFAIL);
 	}
 	return err;
 }