net: add comment for sock_efree() usage

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Acked-by: Alexander Duyck <alexander.h.duyck@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/sock.c

@@ -1655,6 +1655,10 @@ void sock_rfree(struct sk_buff *skb)
 }
 EXPORT_SYMBOL(sock_rfree);
 
+/*
+ * Buffer destructor for skbs that are not used directly in read or write
+ * path, e.g. for error handler skbs. Automatically called from kfree_skb.
+ */
 void sock_efree(struct sk_buff *skb)
 {
 	sock_put(skb->sk);