Re: [PATCH v2 1/4] contrib/vhost-user-blk: avoid g_return_val_if() input validation

[Raphael Norwitz]

On Wed, Dec 2, 2020 at 10:27 AM Stefan Hajnoczi <stefanha@redhat.com> wrote:
>
> Do not validate input with g_return_val_if(). This API is intended for
> checking programming errors and is compiled out with -DG_DISABLE_CHECKS.
>
> Use an explicit if statement for input validation so it cannot
> accidentally be compiled out.
>
> Suggested-by: Markus Armbruster <armbru@redhat.com>
> Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

Reviewed-by: Raphael Norwitz <raphael.norwitz@nutanix.com>

> ---
>  contrib/vhost-user-blk/vhost-user-blk.c | 6 +++++-
>  1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/contrib/vhost-user-blk/vhost-user-blk.c 
> b/contrib/vhost-user-blk/vhost-user-blk.c
> index dc981bf945..60e3c9ed37 100644
> --- a/contrib/vhost-user-blk/vhost-user-blk.c
> +++ b/contrib/vhost-user-blk/vhost-user-blk.c
> @@ -404,7 +404,11 @@ vub_get_config(VuDev *vu_dev, uint8_t *config, uint32_t 
> len)
>      VugDev *gdev;
>      VubDev *vdev_blk;
>
> -    g_return_val_if_fail(len <= sizeof(struct virtio_blk_config), -1);
> +    if (len > sizeof(struct virtio_blk_config)) {
> +        fprintf(stderr, "Invalid get_config len %u, expected <= %zu\n",
> +                len, sizeof(struct virtio_blk_config));
> +        return -1;
> +    }
>
>      gdev = container_of(vu_dev, VugDev, parent);
>      vdev_blk = container_of(gdev, VubDev, parent);
> --
> 2.28.0
>