On Wed, Jul 15, 2020 at 12:55:18PM +0300, Maxim Levitsky wrote:
> Linux kernel only supports logical block sizes which are power of two,
> at least 512 bytes and no more that PAGE_SIZE.
>
> Check this instead of crashing later on.
>
> Note that there is no need to check physical block size since it is
> only a hint, and virtio-blk already only supports power of two values.
>
> Bugzilla link: https://bugzilla.redhat.com/show_bug.cgi?id=1664619
>
> Signed-off-by: Maxim Levitsky <[email protected]>
> ---
> drivers/block/virtio_blk.c | 20 ++++++++++++++++++--
> 1 file changed, 18 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
> index 980df853ee497..36dda31cc4e96 100644
> --- a/drivers/block/virtio_blk.c
> +++ b/drivers/block/virtio_blk.c
> @@ -681,6 +681,12 @@ static const struct blk_mq_ops virtio_mq_ops = {
> static unsigned int virtblk_queue_depth;
> module_param_named(queue_depth, virtblk_queue_depth, uint, 0444);
>
> +
> +static bool virtblk_valid_block_size(unsigned int blksize)
> +{
> + return blksize >= 512 && blksize <= PAGE_SIZE && is_power_of_2(blksize);
> +}
> +
Is this a blk core assumption? in that case, does not this belong
in blk core?
> static int virtblk_probe(struct virtio_device *vdev)
> {
> struct virtio_blk *vblk;
> @@ -809,9 +815,16 @@ static int virtblk_probe(struct virtio_device *vdev)
> err = virtio_cread_feature(vdev, VIRTIO_BLK_F_BLK_SIZE,
> struct virtio_blk_config, blk_size,
> &blk_size);
> - if (!err)
> + if (!err) {
> + if (!virtblk_valid_block_size(blk_size)) {
> + dev_err(&vdev->dev,
> + "%s failure: unsupported logical block size
> %d\n",
> + __func__, blk_size);
> + err = -EINVAL;
> + goto out_cleanup_queue;
> + }
> blk_queue_logical_block_size(q, blk_size);
> - else
> + } else
> blk_size = queue_logical_block_size(q);
>
> /* Use topology information if available */
OK so if we are doing this pls add {} around blk_size =
queue_logical_block_size(q);
too.
> @@ -872,6 +885,9 @@ static int virtblk_probe(struct virtio_device *vdev)
> device_add_disk(&vdev->dev, vblk->disk, virtblk_attr_groups);
> return 0;
>
> +out_cleanup_queue:
> + blk_cleanup_queue(vblk->disk->queue);
> + vblk->disk->queue = NULL;
> out_free_tags:
> blk_mq_free_tag_set(&vblk->tag_set);
> out_put_disk:
> --
> 2.26.2
