Re: [PATCH v5] virtio-blk: Add validation for block size in config space

[Yongji Xie]

On Mon, Oct 4, 2021 at 11:27 PM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>
> On Mon, Aug 09, 2021 at 06:16:09PM +0800, Xie Yongji wrote:
> > An untrusted device might presents an invalid block size
> > in configuration space. This tries to add validation for it
> > in the validate callback and clear the VIRTIO_BLK_F_BLK_SIZE
> > feature bit if the value is out of the supported range.
> >
> > And we also double check the value in virtblk_probe() in
> > case that it's changed after the validation.
> >
> > Signed-off-by: Xie Yongji <xieyongji@xxxxxxxxxxxxx>
>
> So I had to revert this due basically bugs in QEMU.
>
> My suggestion at this point is to try and update
> blk_queue_logical_block_size to BUG_ON when the size
> is out of a reasonable range.
>
> This has the advantage of fixing more hardware, not just virtio.
>

I wonder if it's better to just add a new patch to remove the
virtblk_validate() part. And the check of block size in
virtblk_probe() can be safely removed after the block layer is changed
to validate the block size.

Thanks,
Yongji