From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <stephen@networkplumber.org>
Subject: Re: [Patch net-next v2 3/5] net_sched: act: move
 tcf_hashinfo_init() into tcf_register_action()
Date: Thu, 23 Jan 2014 16:08:59 -0800
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References: <1390516525-8556-1-git-send-email-xiyou.wangcong@gmail.com>
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Cc: netdev@vger.kernel.org, Jamal Hadi Salim <jhs@mojatatu.com>,
	"David S. Miller" <davem@davemloft.net>
To: Cong Wang <xiyou.wangcong@gmail.com>
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On Thu, 23 Jan 2014 14:35:23 -0800
Cong Wang <xiyou.wangcong@gmail.com> wrote:

>  
>  struct tc_action {
>  	void			*priv;
> -	const struct tc_action_ops	*ops;
> +	struct tc_action_ops	*ops;

As much as possible all function tables should be constant.
One of the rootkit tricks is to overwrite a function table entry
at runtime. Granted tc action is a minor corner of the exposed
universe, but this seems a step backwards when the only real
gain is some refactoring/cleanup.