Commit d59f4e1d authored by Zhengchao Shao's avatar Zhengchao Shao Committed by David S. Miller
Browse files

net: sched: htb: remove redundant resource cleanup in htb_init() 



If htb_init() fails, qdisc_create() invokes htb_destroy() to clear
resources. Therefore, remove redundant resource cleanup in htb_init().

Signed-off-by: default avatarZhengchao Shao <shaozhengchao@huawei.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 494f5063

net/sched/sch_htb.c

+9 −27
Original line number Diff line number Diff line
@@ -1102,7 +1102,7 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt, 


	err = qdisc_class_hash_init(&q->clhash);

	if (err < 0)

		goto err_free_direct_qdiscs;

		return err;



	if (tb[TCA_HTB_DIRECT_QLEN])

		q->direct_qlen = nla_get_u32(tb[TCA_HTB_DIRECT_QLEN]);
@@ -1123,8 +1123,7 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt, 
		qdisc = qdisc_create_dflt(dev_queue, &pfifo_qdisc_ops,

					  TC_H_MAKE(sch->handle, 0), extack);

		if (!qdisc) {

			err = -ENOMEM;

			goto err_free_qdiscs;

			return -ENOMEM;

		}



		htb_set_lockdep_class_child(qdisc);
@@ -1142,7 +1141,7 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt, 
	};

	err = htb_offload(dev, &offload_opt);

	if (err)

		goto err_free_qdiscs;

		return err;



	/* Defer this assignment, so that htb_destroy skips offload-related

	 * parts (especially calling ndo_setup_tc) on errors.
@@ -1150,22 +1149,6 @@ static int htb_init(struct Qdisc *sch, struct nlattr *opt, 
	q->offload = true;



	return 0;



err_free_qdiscs:

	for (ntx = 0; ntx < q->num_direct_qdiscs && q->direct_qdiscs[ntx];

	     ntx++)

		qdisc_put(q->direct_qdiscs[ntx]);



	qdisc_class_hash_destroy(&q->clhash);

	/* Prevent use-after-free and double-free when htb_destroy gets called.

	 */

	q->clhash.hash = NULL;

	q->clhash.hashsize = 0;



err_free_direct_qdiscs:

	kfree(q->direct_qdiscs);

	q->direct_qdiscs = NULL;

	return err;

}



static void htb_attach_offload(struct Qdisc *sch)
@@ -1688,13 +1671,12 @@ static void htb_destroy(struct Qdisc *sch) 
	qdisc_class_hash_destroy(&q->clhash);

	__qdisc_reset_queue(&q->direct_queue);



	if (!q->offload)

		return;



	if (q->offload) {

		offload_opt = (struct tc_htb_qopt_offload) {

			.command = TC_HTB_DESTROY,

		};

		htb_offload(dev, &offload_opt);

	}



	if (!q->direct_qdiscs)

		return;