On 20.08.21 10:35, Yufeng Mo wrote:
> In order to support more coalesce parameters through netlink,
> add two new parameter kernel_coal and extack for .set_coalesce
> and .get_coalesce, then some extra info can return to user with
> the netlink API.
>
> Signed-off-by: Yufeng Mo <moyufeng@xxxxxxxxxx>
> Signed-off-by: Huazhong Tan <tanhuazhong@xxxxxxxxxx>
> ---
[...]
> index 81fa36a..f2abc31 100644
> --- a/net/ethtool/ioctl.c
> +++ b/net/ethtool/ioctl.c
> @@ -1619,12 +1619,14 @@ static noinline_for_stack int ethtool_get_coalesce(struct net_device *dev,
> void __user *useraddr)
> {
> struct ethtool_coalesce coalesce = { .cmd = ETHTOOL_GCOALESCE };
> + struct kernel_ethtool_coalesce kernel_coalesce = {};
> int ret;
>
> if (!dev->ethtool_ops->get_coalesce)
> return -EOPNOTSUPP;
>
> - ret = dev->ethtool_ops->get_coalesce(dev, &coalesce);
> + ret = dev->ethtool_ops->get_coalesce(dev, &coalesce, &kernel_coalesce,
> + NULL);
> if (ret)
> return ret;
>
> @@ -1691,19 +1693,26 @@ ethtool_set_coalesce_supported(struct net_device *dev,
> static noinline_for_stack int ethtool_set_coalesce(struct net_device *dev,
> void __user *useraddr)
> {
> + struct kernel_ethtool_coalesce kernel_coalesce = {};
> struct ethtool_coalesce coalesce;
> int ret;
>
> - if (!dev->ethtool_ops->set_coalesce)
> + if (!dev->ethtool_ops->set_coalesce && !dev->ethtool_ops->get_coalesce)
> return -EOPNOTSUPP;
>
This needs to be
if (!set_coalesce || !get_coalesce)
return -EOPNOTSUPP;
Otherwise you end up calling a NULL pointer below if just _one_ of the
callbacks is available.
> + ret = dev->ethtool_ops->get_coalesce(dev, &coalesce, &kernel_coalesce,
> + NULL);
> + if (ret)
> + return ret;
> +
> if (copy_from_user(&coalesce, useraddr, sizeof(coalesce)))
> return -EFAULT;
>
> if (!ethtool_set_coalesce_supported(dev, &coalesce))
> return -EOPNOTSUPP;
>
> - ret = dev->ethtool_ops->set_coalesce(dev, &coalesce);
> + ret = dev->ethtool_ops->set_coalesce(dev, &coalesce, &kernel_coalesce,
> + NULL);
> if (!ret)
> ethtool_notify(dev, ETHTOOL_MSG_COALESCE_NTF, NULL);
> return ret;
>
