Commit a0527ee2 authored by Stanislav Fomichev's avatar Stanislav Fomichev Committed by Jakub Kicinski
Browse files

net: hold netdev instance lock during qdisc ndo_setup_tc 



Qdisc operations that can lead to ndo_setup_tc might need
to have an instance lock. Add netdev_lock_ops/netdev_unlock_ops
invocations for all psched_rtnl_msg_handlers operations.

Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: Saeed Mahameed <saeed@kernel.org>
Reviewed-by: default avatarJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: default avatarStanislav Fomichev <sdf@fomichev.me>
Link: https://patch.msgid.link/20250305163732.2766420-5-sdf@fomichev.me


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 7c79cff9

net/sched/sch_api.c

+24 −4
Original line number Diff line number Diff line
@@ -1279,9 +1279,11 @@ static struct Qdisc *qdisc_create(struct net_device *dev, 
			 * We replay the request because the device may

			 * go away in the mean time.

			 */

			netdev_unlock_ops(dev);

			rtnl_unlock();

			request_module(NET_SCH_ALIAS_PREFIX "%s", name);

			rtnl_lock();

			netdev_lock_ops(dev);

			ops = qdisc_lookup_ops(kind);

			if (ops != NULL) {

				/* We will try again qdisc_lookup_ops,
@@ -1591,7 +1593,11 @@ static int tc_get_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 
	if (!dev)

		return -ENODEV;



	return __tc_get_qdisc(skb, n, extack, dev, tca, tcm);

	netdev_lock_ops(dev);

	err = __tc_get_qdisc(skb, n, extack, dev, tca, tcm);

	netdev_unlock_ops(dev);



	return err;

}



static bool req_create_or_replace(struct nlmsghdr *n)
@@ -1828,7 +1834,9 @@ static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n, 
		return -ENODEV;



	replay = false;

	netdev_lock_ops(dev);

	err = __tc_modify_qdisc(skb, n, extack, dev, tca, tcm, &replay);

	netdev_unlock_ops(dev);

	if (replay)

		goto replay;
@@ -1919,17 +1927,23 @@ static int tc_dump_qdisc(struct sk_buff *skb, struct netlink_callback *cb) 
			s_q_idx = 0;

		q_idx = 0;



		netdev_lock_ops(dev);

		if (tc_dump_qdisc_root(rtnl_dereference(dev->qdisc),

				       skb, cb, &q_idx, s_q_idx,

				       true, tca[TCA_DUMP_INVISIBLE]) < 0)

				       true, tca[TCA_DUMP_INVISIBLE]) < 0) {

			netdev_unlock_ops(dev);

			goto done;

		}



		dev_queue = dev_ingress_queue(dev);

		if (dev_queue &&

		    tc_dump_qdisc_root(rtnl_dereference(dev_queue->qdisc_sleeping),

				       skb, cb, &q_idx, s_q_idx, false,

				       tca[TCA_DUMP_INVISIBLE]) < 0)

				       tca[TCA_DUMP_INVISIBLE]) < 0) {

			netdev_unlock_ops(dev);

			goto done;

		}

		netdev_unlock_ops(dev);



cont:

		idx++;
@@ -2308,7 +2322,11 @@ static int tc_ctl_tclass(struct sk_buff *skb, struct nlmsghdr *n, 
	if (!dev)

		return -ENODEV;



	return __tc_ctl_tclass(skb, n, extack, dev, tca, tcm);

	netdev_lock_ops(dev);

	err = __tc_ctl_tclass(skb, n, extack, dev, tca, tcm);

	netdev_unlock_ops(dev);



	return err;

}



struct qdisc_dump_args {
@@ -2426,7 +2444,9 @@ static int tc_dump_tclass(struct sk_buff *skb, struct netlink_callback *cb) 
	if (!dev)

		return 0;



	netdev_lock_ops(dev);

	err = __tc_dump_tclass(skb, cb, tcm, dev);

	netdev_unlock_ops(dev);



	dev_put(dev);