netdev - Re: [PATCH 2/4] vDPA: only report driver features if FEATURES

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 20 Sep 2022 10:16:33 +0800
From:   Jason Wang <jasowang@...hat.com>
To:     Zhu Lingshan <lingshan.zhu@...el.com>
Cc:     mst <mst@...hat.com>,
        virtualization <virtualization@...ts.linux-foundation.org>,
        netdev <netdev@...r.kernel.org>, kvm <kvm@...r.kernel.org>
Subject: Re: [PATCH 2/4] vDPA: only report driver features if FEATURES_OK is set

On Fri, Sep 9, 2022 at 5:05 PM Zhu Lingshan <lingshan.zhu@...el.com> wrote:
>
> vdpa_dev_net_config_fill() should only report driver features
> to userspace after features negotiation is done.
>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@...el.com>
> ---
>  drivers/vdpa/vdpa.c | 13 +++++++++----
>  1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
> index 798a02c7aa94..29d7e8858e6f 100644
> --- a/drivers/vdpa/vdpa.c
> +++ b/drivers/vdpa/vdpa.c
> @@ -819,6 +819,7 @@ static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *ms
>         struct virtio_net_config config = {};
>         u64 features_device, features_driver;
>         u16 val_u16;
> +       u8 status;
>
>         vdev->config->get_config(vdev, 0, &config, sizeof(config));
>
> @@ -834,10 +835,14 @@ static int vdpa_dev_net_config_fill(struct vdpa_device *vdev, struct sk_buff *ms
>         if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MTU, val_u16))
>                 return -EMSGSIZE;
>
> -       features_driver = vdev->config->get_driver_features(vdev);
> -       if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features_driver,
> -                             VDPA_ATTR_PAD))
> -               return -EMSGSIZE;
> +       /* only read driver features after the feature negotiation is done */
> +       status = vdev->config->get_status(vdev);
> +       if (status & VIRTIO_CONFIG_S_FEATURES_OK) {

Any reason this is not checked in its caller as what it used to do before?

Thanks

> +               features_driver = vdev->config->get_driver_features(vdev);
> +               if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES, features_driver,
> +                                     VDPA_ATTR_PAD))
> +                       return -EMSGSIZE;
> +       }
>
>         features_device = vdev->config->get_device_features(vdev);
>
> --
> 2.31.1
>