Make sure the decision whether an index received through a callback is valid or not consults the negotiated features. The motivation for this was due to a case encountered where I shut down the VM. After the reset operation was called features were already clear, I got get_vq_state() call which caused out array bounds access since is_index_valid() reported the index value. So this is more of not hit a bug since the call shouldn't have been made first place. Signed-off-by: Eli Cohen <elic@nvidia.com> Link: https://lore.kernel.org/r/20220111183400.38418-4-elic@nvidia.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Si-Wei Liu<si-wei.liu@oracle.com> Acked-by: Jason Wang <jasowang@redhat.com>