Re: [RFC V2 PATCH 8/12] UIO/Hyper-V: Not load UIO HV driver in the isolation VM.

From: Greg KH
Date: Wed Apr 14 2021 - 11:36:54 EST


On Wed, Apr 14, 2021 at 11:20:19PM +0800, Tianyu Lan wrote:
> Hi Greg:
> Thanks for your review.
>
> On 4/14/2021 12:00 AM, Greg KH wrote:
> > On Tue, Apr 13, 2021 at 11:22:13AM -0400, Tianyu Lan wrote:
> > > From: Tianyu Lan <Tianyu.Lan@xxxxxxxxxxxxx>
> > >
> > > UIO HV driver should not load in the isolation VM for security reason.
> >
> > Why? I need a lot more excuse than that.
>
> The reason is that ring buffers have been marked as visible to host.
> UIO driver will expose these buffers to user space and user space
> driver hasn't done some secure check for data from host. This
> is considered as insecure in isolation VM.

But as this is a VM choice, why did the VM mark those as visible in the
first place?

thanks,

greg k-h