Re: [PATCH 00/16] [RFC PATCH] Signed kexec support

Greg KH
2013-09-12T03:40:39Z

On Tue, Sep 10, 2013 at 05:44:15PM -0400, Vivek Goyal wrote:
> Hi,
>
> Matthew has been posting patches to lock down kernel either due to
> secureboot requirements or because of signed modules with signing
> enforced. In kernel lock down mode, kexec will be disabled and that
> means kdump will not work either.
>
> These patches sign /sbin/kexec and kernel verifies the signature
> and allows loading a kernel if signature verification is successful.
> IOW, trust is extended to validly signed user space.
>
> Currently it works only for statically linked applications.

That's a really big restriction, pretty much making it not workable for
distros at the moment to use.

Any chance to change this in the future? Or just rely on the existing
"signed binaries" functionality we have in the kernel today for the
kexec binary as well? Wouldn't that be simpler?

thanks,

greg k-h