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Date: Thu, 23 Dec 2010 18:01:14 +0800
From: Cong Wang <amwang@redhat.com>
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To: Andrew Morton <akpm@linux-foundation.org>
CC: linux-kernel@vger.kernel.org, Neil Horman <nhorman@tuxdriver.com>,
        WANG Cong <xiyou.wangcong@gmail.com>,
        Frederic Weisbecker <fweisbec@gmail.com>,
        Wu Fengguang <fengguang.wu@intel.com>,
        Dan Carpenter <error27@gmail.com>, Tejun Heo <tj@kernel.org>,
        Eugene Teo <eugene@redhat.com>
Subject: Re: [RFC Patch] kcore: restrict access to the whole memory
References: <1293016926-1714-1-git-send-email-amwang@redhat.com> <20101222150209.8e18afa7.akpm@linux-foundation.org>
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于 2010年12月23日 07:02, Andrew Morton 写道:
> On Wed, 22 Dec 2010 19:21:59 +0800
> Amerigo Wang<amwang@redhat.com>  wrote:
>
>> This patch restricts /proc/kcore from accessing the whole memory,
>> instead, only an ELF header can be read.
>>
>> The initial patch was done by Vivek.
>
> Getting a bit tired of this.
>
> Are we supposed to be mind-readers?  How else are we to work out why
> you think Linux needs this feature?  What problems it solves?  What
> applications are expected to break and what the breakage patterns are?
> Why the benefits are worth the maintenance costs and the risk of
> breakage?  Why it's done with a config option and not a boot-time or
> runtime tunable?
>

Oh, sorry, I forgot to mention this is for security reasons,
I am adding Eugene into Cc so that he can explain more about this.

Yeah, I thought about sysctl too, but it is really weird for me
to control /proc/kcore contents via an sysctl file, I think
an Kconfig is enough.

Thanks!