Re: [PATCH 0/6] MODSIGN: Kernel module signing

[David Lang]

On Thu, 15 Feb 2007, Roman Zippel wrote:

> On Thu, 15 Feb 2007, David Howells wrote:
>
> > It is possible to protect /dev/mem and /dev/kmem or make them unavailable and
> > it is possible to protect the kernel's memory whilst it is running (provided
> > you don't have nommu or broken hardware and you don't let userspace concoct any
> > DMA request it likes) which mostly closes those other vectors I mentioned.
> > This isn't something I intended to look at with this patch.  Those are separate
> > holes.
>
> Exactly and as long as there are these holes, these patches are only
> kernel bloat. The simple verification can also be done in userspace and
> module signing offers no real security.
> What real value do these patches provide, that can't be reached via other
> means? Who else than distributions would be interested in this? Pretty
> much any use you initially mentioned can be done in simpler ways, e.g.
> anyone afraid of modules simply disables module loading completely.

this issue, and these holes keep comeing up in discussions, why can't these 
holes be closed? I seem to remember seeing patches that would remove /dev/kmem 
being sent to the list, but they weren't accepted into the kernel (and I seem to 
remember people being against the concept of removeing them, not against 
techincal details of the patches. but this was many years ago)

at one point I remember hearing that X required raw /dev/kmem, but for servers 
you don't need/want X anyway, so this is a useful option even if X doesn't get 
fixed.

David Lang
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/