Re: [PATCH 3/3] x86/sev: The code for returning to user space is also in syscall gap

From: Lai Jiangshan
Date: Tue Apr 12 2022 - 09:14:40 EST


On Wed, Dec 15, 2021 at 5:51 AM Borislav Petkov <bp@xxxxxxxxx> wrote:
>
> + Tom and leaving the whole mail un-trimmed for him.
>
> On Mon, Dec 13, 2021 at 12:22:15PM +0800, Lai Jiangshan wrote:
> > From: Lai Jiangshan <laijs@xxxxxxxxxxxxxxxxx>
> >
> > When returning to user space, the %rsp is user controlled value.
>
> And?
>
> I'd expect to see here some text analyzing the couple of instructions
> between those new labels you've added and whether a #VC can happen
> there.


Hello, Borislav

I resent the patch with an updated changelog mainly copied from
Joerg's reply.

https://lore.kernel.org/lkml/20220412124909.10467-1-jiangshanlai@xxxxxxxxx/


The other two patches in this patchset are omitted since they
make less sense which only harms only when the system owner
is deliberately doing stupid things.

thanks
Lai