net_sched: fix a memory leak in tc action

Fixes: ddf97ccdd7cb ("net_sched: add network namespace support for tc actions")
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/act_api.h

@@ -135,6 +135,7 @@ void tcf_hashinfo_destroy(const struct tc_action_ops *ops,
 static inline void tc_action_net_exit(struct tc_action_net *tn)
 {
 	tcf_hashinfo_destroy(tn->ops, tn->hinfo);
+	kfree(tn->hinfo);
 }
 
 int tcf_generic_walker(struct tc_action_net *tn, struct sk_buff *skb,