Re: [PATCH 1/4] kaslr: check user's config too when handle relocations

Vivek Goyal
2014-09-10T15:39:03Z

On Wed, Sep 10, 2014 at 11:27:16PM +0800, Baoquan He wrote:
> On 09/10/14 at 11:05am, Vivek Goyal wrote:
> > On Wed, Sep 10, 2014 at 07:41:38AM -0700, Kees Cook wrote:
> > > On Wed, Sep 10, 2014 at 7:30 AM, Vivek Goyal <vgoyal@redhat.com> wrote:
> > > > So I would suggest that test and repost the other patch with proper changelog
> > > > and that might be sufficient for now. Only other thing we will need is
> > > > Kees's patch for avoiding setup data regions in kaslr.
> > >
> > > If someone can confirm that my patch works, I can request x86 pull it.
> > >
> > > Currently living here:
> > > https://git.kernel.org/cgit/linux/kernel/git/kees/linux.git/log/?h=kaslr
> > >
> >
> > Bao,
> >
> > Can you please test Kees's patch and provide feedback.
>
> I can only use a trick by setting the E820_MAX to a very small number,
> say 10 in kexec-tools. Then extra memory regions will be added into
> setup data. Sufficient real test can't be taken by me since lack of
> machine.

I think modifying kexec-tools test should be good. Also we prepare
an kexec specific data blob for EFI machines and pass to second
kernel through setup_data. We can put some printk and make sure
this patch avoids that region.

Thanks
Vivek