Re: [PATCH 03/10] kvmclock: Use free_decrypted_pages()

From: Edgecombe, Rick P
Date: Wed Oct 18 2023 - 11:57:44 EST


On Tue, 2023-10-17 at 22:20 -0700, Kuppuswamy Sathyanarayanan wrote:
>
>
> On 10/17/2023 1:24 PM, Rick Edgecombe wrote:
> > On TDX it is possible for the untrusted host to cause
> > set_memory_encrypted() or set_memory_decrypted() to fail such that
> > an
> > error is returned and the resulting memory is shared. Callers need
> > to take
> > care to handle these errors to avoid returning decrypted (shared)
> > memory to
> > the page allocator, which could lead to functional or security
> > issues.
> >
> > Kvmclock could free decrypted/shared pages if
> > set_memory_decrypted() fails.
> > Use the recently added free_decrypted_pages() to avoid this.
> >
> > Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> > Cc: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> > Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> > Cc: kvm@xxxxxxxxxxxxxxx
> > Signed-off-by: Rick Edgecombe <rick.p.edgecombe@xxxxxxxxx>
> > ---
>
> Since it a fix, do you want to add Fixes tag?
>
> Otherwise, it looks good to me.
>
> Reviewed-by: Kuppuswamy Sathyanarayanan
> <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

Thanks. Yes, the thinking was to mark all these for stable, but some
patches are still RFC for this version. I'll add it for all non-RFC
ones in the next version.