Re: [QUESTION] Kprobes as a module?

From: Namhyung Kim
Date: Tue May 15 2012 - 21:46:19 EST


Hi,

On Tue, 15 May 2012 21:18:25 +0900, Masami Hiramatsu wrote:
> No, actually you can't make it as a module.ãThere are
> two major reasons.
> - ftrace depends on the kprobes now.
> - int3 handling routine is deeply depends on
> the architecture. This includes text modifying code.
>
> Thus, if you separate the kprobes into module, that means
> you need to expose more ugly interface of self modifying
> for kernel modules.
>

I see.


> (2012/05/15 17:34), Namhyung Kim wrote:
>> Hi,
>>
>> On Tue, 15 May 2012 16:31:42 +0800, Cong Wang wrote:
>>> On 05/15/2012 04:24 PM, Namhyung Kim wrote:
>>>> Hi,
>>>>
>>>> Probably a dumb question :).
>>>> What prevents the kprobes from being built as a module? We want to use
>>>> the kprobes on our systems, but some guys worried about potential
>>>> security problems. So it'd be great if we can enable/load kprobes as
>>>> needed and then disable/unload after using it. Is it a possible senario?
>
> BTW, I'm not sure what the potential security problems on that?
> kprobes itself can be used only from kernel modules(except ftrace).
> If someone compromises kernel with kernel module, he doesn't need
> kprobes at all. They just can do anything they want. :)
>

Nevermind, it seems they just worried about what they don't know
exactly. Anyway, thanks for your answer.

Namhyung
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