netdev - Re: [PATCH net-next v8 1/5] net/sched: Introduce tc block netdev tracking infra

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Thu, 28 Dec 2023 13:50:29 +0200
From: Ido Schimmel <idosch@...sch.org>
To: Victor Nogueira <victor@...atatu.com>
Cc: jhs@...atatu.com, davem@...emloft.net, edumazet@...gle.com,
	kuba@...nel.org, pabeni@...hat.com, xiyou.wangcong@...il.com,
	jiri@...nulli.us, mleitner@...hat.com, vladbu@...dia.com,
	paulb@...dia.com, pctammela@...atatu.com, netdev@...r.kernel.org,
	kernel@...atatu.com
Subject: Re: [PATCH net-next v8 1/5] net/sched: Introduce tc block netdev
 tracking infra

On Tue, Dec 19, 2023 at 03:16:19PM -0300, Victor Nogueira wrote:
> +static int qdisc_block_add_dev(struct Qdisc *sch, struct net_device *dev,
> +			       struct netlink_ext_ack *extack)
> +{
> +	const struct Qdisc_class_ops *cl_ops = sch->ops->cl_ops;
> +	struct tcf_block *block;
> +	int err;
> +
> +	block = cl_ops->tcf_block(sch, TC_H_MIN_INGRESS, NULL);

Another problem, shouldn't there be a check that these operations are
actually implemented? The following now crashes with a NULL pointer
dereference:

# tc qdisc replace dev swp1 root handle 1: tbf rate 1Mbit burst 256k limit 1M

> +	if (block) {
> +		err = xa_insert(&block->ports, dev->ifindex, dev, GFP_KERNEL);
> +		if (err) {
> +			NL_SET_ERR_MSG(extack,
> +				       "ingress block dev insert failed");
> +			return err;
> +		}
> +	}
> +
> +	block = cl_ops->tcf_block(sch, TC_H_MIN_EGRESS, NULL);
> +	if (block) {
> +		err = xa_insert(&block->ports, dev->ifindex, dev, GFP_KERNEL);
> +		if (err) {
> +			NL_SET_ERR_MSG(extack,
> +				       "Egress block dev insert failed");
> +			goto err_out;
> +		}
> +	}
> +
> +	return 0;
> +
> +err_out:
> +	block = cl_ops->tcf_block(sch, TC_H_MIN_INGRESS, NULL);
> +	if (block)
> +		xa_erase(&block->ports, dev->ifindex);
> +
> +	return err;
> +}
> +
>  static int qdisc_block_indexes_set(struct Qdisc *sch, struct nlattr **tca,
>  				   struct netlink_ext_ack *extack)
>  {
> @@ -1350,6 +1387,10 @@ static struct Qdisc *qdisc_create(struct net_device *dev,
>  	qdisc_hash_add(sch, false);
>  	trace_qdisc_create(ops, dev, parent);
>  
> +	err = qdisc_block_add_dev(sch, dev, extack);
> +	if (err)
> +		goto err_out4;
> +
>  	return sch;
>  
>  err_out4: