Re: [PATCH V3 08/11] kexec: Disable at runtime if the kernelenforces module loading restrictions
From: Matthew Garrett
Date: Sun Sep 08 2013 - 12:59:50 EST
On Sun, 2013-09-08 at 09:39 -0700, Greg KH wrote:
> But I want, for other reasons (i.e. safety in layers), signed kernel
> modules. I also might actually want some debugfs files in some random
> driver (like this series removes).
You want a configuration that makes no sense. There's no reason that the
kernel should make that easy.
> Heck, look at Red Hat. They have been shipping signed kernel modules
> for _years_ and yet they do not disable kexec. Have they been "doing it
> wrong" all of this time? Perhaps people want signed modules just for
> support reasons, not "security" reasons.
Then they do what Red Hat does and don't set CONFIG_SIG_ENFORCE.
> Don't take away those options.
Where's the option to let me let unprivileged users set random MSRs?
Where's the option to let root disable STRICT_DEVMEM at runtime? We
don't offer these options because *they make no sense*. Locking your
door while leaving your window open may make you feel better, but it
doesn't improve the security of your house.
--
Matthew Garrett <matthew.garrett@xxxxxxxxxx>
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