Commit f98ebd47 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

net: sched: avoid writing on noop_qdisc 



While noop_qdisc.gso_skb and noop_qdisc.skb_bad_txq are not used
in other places, it seems not correct to overwrite their fields
in dev_init_scheduler_queue().

noop_qdisc is essentially a shared and read-only object, even if
it is not marked as const because of some implementation detail.

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent d8a66aa2

net/sched/sch_generic.c

+12 −2
Original line number Diff line number Diff line
@@ -572,6 +572,18 @@ struct Qdisc noop_qdisc = { 
	.dev_queue	=	&noop_netdev_queue,

	.running	=	SEQCNT_ZERO(noop_qdisc.running),

	.busylock	=	__SPIN_LOCK_UNLOCKED(noop_qdisc.busylock),

	.gso_skb = {

		.next = (struct sk_buff *)&noop_qdisc.gso_skb,

		.prev = (struct sk_buff *)&noop_qdisc.gso_skb,

		.qlen = 0,

		.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.gso_skb.lock),

	},

	.skb_bad_txq = {

		.next = (struct sk_buff *)&noop_qdisc.skb_bad_txq,

		.prev = (struct sk_buff *)&noop_qdisc.skb_bad_txq,

		.qlen = 0,

		.lock = __SPIN_LOCK_UNLOCKED(noop_qdisc.skb_bad_txq.lock),

	},

};

EXPORT_SYMBOL(noop_qdisc);
@@ -1273,8 +1285,6 @@ static void dev_init_scheduler_queue(struct net_device *dev, 


	rcu_assign_pointer(dev_queue->qdisc, qdisc);

	dev_queue->qdisc_sleeping = qdisc;

	__skb_queue_head_init(&qdisc->gso_skb);

	__skb_queue_head_init(&qdisc->skb_bad_txq);

}



void dev_init_scheduler(struct net_device *dev)

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