Re: [PATCH v3 0/8] vhost: Reset batched descriptors on SET_VRING_BASE call

Eugenio Perez Martin
2020-04-01T18:41:08Z

On Wed, Apr 1, 2020 at 9:19 AM Christian Borntraeger
<borntraeger@de.ibm.com> wrote:
>
> On 31.03.20 21:27, Eugenio Pérez wrote:
> > Vhost did not reset properly the batched descriptors on SET_VRING_BASE
> > event. Because of that, is possible to return an invalid descriptor to
> > the guest.
> >
> > This series ammend this, resetting them every time backend changes, and
> > creates a test to assert correct behavior. To do that, they need to
> > expose a new function in virtio_ring, virtqueue_reset_free_head, only
> > on test code.
> >
> > Another useful thing would be to check if mutex is properly get in
> > vq private_data accessors. Not sure if mutex debug code allow that,
> > similar to C++ unique lock::owns_lock. Not acquiring in the function
> > because caller code holds the mutex in order to perform more actions.
>
>
>
> >
> > v3:
> > * Rename accesors functions.
> > * Make scsi and test use the accesors too.
> >
> > v2:
> > * Squashed commits.
> > * Create vq private_data accesors (mst).
> >
> > This is meant to be applied on top of
> > c4f1c41a6094582903c75c0dcfacb453c959d457 in
> > git.kernel.org/pub/scm/linux/kernel/git/mst/vhost.git.
>
>
> A quick test on s390 looks good.
>

Really good to know :).

Would it be possible to investigate when qemu launches the offending ioctls?

Thanks!