net: also make sch_handle_egress() drop monitor ready

Follow-up for 8a3a4c6e7b34 ("net: make sch_handle_ingress() drop
monitor ready") to also make the egress side drop monitor ready.

Also here only TC_ACT_SHOT is a clear indication that something
went wrong. Hence don't provide false positives to drop monitors
such as 'perf record -e skb:kfree_skb ...'.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/dev.c

@@ -3186,12 +3186,12 @@ sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
 	case TC_ACT_SHOT:
 		qdisc_qstats_cpu_drop(cl->q);
 		*ret = NET_XMIT_DROP;
-		goto drop;
+		kfree_skb(skb);
+		return NULL;
 	case TC_ACT_STOLEN:
 	case TC_ACT_QUEUED:
 		*ret = NET_XMIT_SUCCESS;
-drop:
-		kfree_skb(skb);
+		consume_skb(skb);
 		return NULL;
 	case TC_ACT_REDIRECT:
 		/* No need to push/pop skb's mac_header here on egress! */