Re: [PATCH 2/2] Add dev.mem.restricted sysctl

From: Arjan van de Ven
Date: Sat Nov 15 2008 - 22:48:38 EST


On Sun, 16 Nov 2008 01:03:43 +0100
Bernhard Walle <bwalle@xxxxxxx> wrote:

> When CONFIG_STRICT_DEVMEM is set, live debugging is not possible with
> the crash utility (see http://people.redhat.com/~anderson). For
> distributors who ship a generic kernel it's difficult: Disabling
> CONFIG_STRICT_DEVMEM is possible, but in general the protection
> provided by CONFIG_STRICT_DEVMEM is useful. However, live debugging
> should be still neceessary.
>
> This patch now adds a dev.mem.restricted sysctl that defaults to 0
> (off). When set to 1 (on), /dev/mem access is unrestricted and crash
> can be used.
>


sounds like a really bad idea to me.
If you want to use /dev/mem like this, don't enable the config option
to restrict it. Really.


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Arjan van de Ven Intel Open Source Technology Centre
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