Re: [PATCH 3/6] Drivers: hv: vmbus: Avoid double fetch of payload_size in vmbus_on_msg_dpc()

[Andrea Parri]

On Sun, Dec 06, 2020 at 05:14:18PM +0000, Michael Kelley wrote:
> From: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx> Sent: Wednesday, November 18, 2020 6:37 AM
> > 
> > vmbus_on_msg_dpc() double fetches from payload_size.  The double fetch
> > can lead to a buffer overflow when (mem)copying the hv_message object.
> > Avoid the double fetch by saving the value of payload_size into a local
> > variable.
> 
> Similar comment here about providing some brief context in the commit
> message on the problem that we are guarding against by removing the
> double fetch.

Will expand.


> 
> I could see combining this patch with the previous one since the
> motivation and pattern of the changes are exactly the same, just for
> two different fields.

Will consider this suggestion for v3.  Please see v2 for a related
discussion.

  Andrea