Re: [PATCH v6 1/3] Drivers: hv: vmbus: Add vmbus_requestor data structure for VMBus hardening

[Wei Liu]

On Thu, Jul 23, 2020 at 01:24:03AM +0000, Michael Kelley wrote:
> From: Andres Beltran <lkmlabelt@xxxxxxxxx> Sent: Wednesday, July 22, 2020 3:39 PM
> > 
> > Currently, VMbus drivers use pointers into guest memory as request IDs
> > for interactions with Hyper-V. To be more robust in the face of errors
> > or malicious behavior from a compromised Hyper-V, avoid exposing
> > guest memory addresses to Hyper-V. Also avoid Hyper-V giving back a
> > bad request ID that is then treated as the address of a guest data
> > structure with no validation. Instead, encapsulate these memory
> > addresses and provide small integers as request IDs.
> > 
> > Signed-off-by: Andres Beltran <lkmlabelt@xxxxxxxxx>
> > ---
> > Changes in v6:
> > 	- Offset request IDs by 1 keeping the original initialization
> > 	  code.
> > Changes in v5:
> >         - Add support for unsolicited messages sent by the host with a
> >           request ID of 0.
> > Changes in v4:
> >         - Use channel->rqstor_size to check if rqstor has been
> >           initialized.
> > Changes in v3:
> >         - Check that requestor has been initialized in
> >           vmbus_next_request_id() and vmbus_request_addr().
> > Changes in v2:
> >         - Get rid of "rqstor" variable in __vmbus_open().
> > 
> >  drivers/hv/channel.c   | 170 +++++++++++++++++++++++++++++++++++++++++
> >  include/linux/hyperv.h |  21 +++++
> >  2 files changed, 191 insertions(+)
> 
> Tested-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>
> Reviewed-by: Michael Kelley <mikelley@xxxxxxxxxxxxx>

Applied to hyperv-next. Thanks.