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Date: Thu, 27 Nov 2025 15:36:44 -0800
From: Jakub Kicinski <kuba@kernel.org>
To: Xiang Mei <xmei5@asu.edu>
Cc: security@kernel.org, netdev@vger.kernel.org, toke@toke.dk,
 xiyou.wangcong@gmail.com, cake@lists.bufferbloat.net, bestswngs@gmail.com
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Subject: [Cake] Re: [PATCH net v7 1/2] net/sched: sch_cake: Fix incorrect qlen reduction in cake_drop
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On Wed, 26 Nov 2025 12:45:12 -0700 Xiang Mei wrote:
> In cake_drop(), qdisc_tree_reduce_backlog() is used to update the qlen
> and backlog of the qdisc hierarchy. Its caller, cake_enqueue(), assumes
> that the parent qdisc will enqueue the current packet. However, this
> assumption breaks when cake_enqueue() returns NET_XMIT_CN: the parent
> qdisc stops enqueuing current packet, leaving the tree qlen/backlog
> accounting inconsistent. This mismatch can lead to a NULL dereference
> (e.g., when the parent Qdisc is qfq_qdisc).

This series does not apply, please rebase on netdev/net/main.
-- 
pw-bot: cr