netdev - Re: size overflow in function qdisc_tree_decrease_qlen net/sched/sch

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]

Message-ID: <1448996964.16994.2.camel@edumazet-glaptop2.roam.corp.google.com>
Date:	Tue, 01 Dec 2015 11:09:24 -0800
From:	Eric Dumazet <eric.dumazet@...il.com>
To:	Cong Wang <cwang@...pensource.com>
Cc:	pageexec@...email.hu, Daniele Fucini <dfucini@...il.com>,
	netdev <netdev@...r.kernel.org>,
	Jamal Hadi Salim <jhs@...atatu.com>,
	David Miller <davem@...emloft.net>, spender@...ecurity.net,
	re.emese@...il.com
Subject: Re: size overflow in function qdisc_tree_decrease_qlen
 net/sched/sch_api.c

On Tue, 2015-12-01 at 10:43 -0800, Cong Wang wrote:

> This smells hacky... Another way to fix this is to hold the qdisc tree
> lock in mq_dump(), since it is not a hot path (comparing with
> enqueue/dequeue)?

Really ? Which qdisc tree lock will protect you exactly ???

Whole point of MQ is that each TX queue has its own lock.

So multiple cpus can call qdisc_tree_decrease_qlen() at the same time,
holding their own lock.

Clearly modifying mq 'data' is wrong.


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html