Commit aa3fab01 authored by David S. Miller's avatar David S. Miller
Browse files

Merge branch 'net_sched-redundant-resource-cleanups'



Zhengchao Shao says:

====================
net: sched: remove redundant resource cleanup when init() fails

qdisc_create() calls .init() to initialize qdisc. If the initialization
fails, qdisc_create() will call .destroy() to release resources.
====================

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parents 40c79ce1 d59f4e1d
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+8 −17
Original line number Diff line number Diff line
@@ -478,26 +478,24 @@ static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt,
	if (opt) {
		err = fq_codel_change(sch, opt, extack);
		if (err)
			goto init_failure;
			return err;
	}

	err = tcf_block_get(&q->block, &q->filter_list, sch, extack);
	if (err)
		goto init_failure;
		return err;

	if (!q->flows) {
		q->flows = kvcalloc(q->flows_cnt,
				    sizeof(struct fq_codel_flow),
				    GFP_KERNEL);
		if (!q->flows) {
			err = -ENOMEM;
			goto init_failure;
		}
		if (!q->flows)
			return -ENOMEM;

		q->backlogs = kvcalloc(q->flows_cnt, sizeof(u32), GFP_KERNEL);
		if (!q->backlogs) {
			err = -ENOMEM;
			goto alloc_failure;
		}
		if (!q->backlogs)
			return -ENOMEM;

		for (i = 0; i < q->flows_cnt; i++) {
			struct fq_codel_flow *flow = q->flows + i;

@@ -510,13 +508,6 @@ static int fq_codel_init(struct Qdisc *sch, struct nlattr *opt,
	else
		sch->flags &= ~TCQ_F_CAN_BYPASS;
	return 0;

alloc_failure:
	kvfree(q->flows);
	q->flows = NULL;
init_failure:
	q->flows_cnt = 0;
	return err;
}

static int fq_codel_dump(struct Qdisc *sch, struct sk_buff *skb)
+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;