[PATCH] taskstats: fix sk_buff leak

'return genlmsg_cancel()' in taskstats_user_cmd/taskstats_exit_send
potentially leaks a skb.  Unless we pass 'rep_skb' to the netlink layer
we own sk_buff.  This means we should always do kfree_skb() on failure.

[ Thomas acked and pointed out missing return value in original version ]
Signed-off-by: Oleg Nesterov <oleg@tv-sign.ru>
Acked-by: Thomas Graf <tgraf@suug.ch>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Shailabh Nagar <nagar@watson.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: Jay Lan <jlan@sgi.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/taskstats.c

@@ -411,7 +411,7 @@ static int taskstats_user_cmd(struct sk_buff *skb, struct genl_info *info)
 	return send_reply(rep_skb, info->snd_pid);
 
 nla_put_failure:
-	return genlmsg_cancel(rep_skb, reply);
+	rc = genlmsg_cancel(rep_skb, reply);
 err:
 	nlmsg_free(rep_skb);
 	return rc;
@@ -507,7 +507,6 @@ void taskstats_exit_send(struct task_struct *tsk, struct taskstats *tidstats,
 
 nla_put_failure:
 	genlmsg_cancel(rep_skb, reply);
-	goto ret;
 err_skb:
 	nlmsg_free(rep_skb);
 ret: