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Subject: Re: [PATCH] net: cgroup: fix out of bounds accesses
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Neil Horman <nhorman@tuxdriver.com>
Cc: David Miller <davem@davemloft.net>, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, lizefan@huawei.com, tj@kernel.org,
        Gao feng <gaofeng@cn.fujitsu.com>
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Date: Mon, 09 Jul 2012 13:50:52 +0200
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On Mon, 2012-07-09 at 07:01 -0400, Neil Horman wrote:

> Thank you for doing this Eric, Gao.  Just to be sure (I asked in the previous
> thread), would it be better to avoid the length check in skb_update_prio, and
> instead update the netdev tables to be long enough in cgrp_create and in
> netprio_device_event on device registration?

Yes probably, and it is even needed because extend_netdev_table() can
acutally fail to expand the table if kzalloc() returned NULL.

Current code just ignores this allocation failure so we also can crash
in write_priomap()