Re: [PATCH net-next V6 03/14] bridge: Validate that vlan is permitted on ingress

[Shmulik Ladkani <shmulik.ladkani@gmail.com>]

Hi Vlad,

On Wed, 16 Jan 2013 13:17:58 -0500 Vlad Yasevich <vyasevic@redhat.com> wrote:
> @@ -45,6 +45,9 @@ netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
>  	brstats->tx_bytes += skb->len;
>  	u64_stats_update_end(&brstats->syncp);
>  
> +	if (!br_allowed_ingress(&br->vlan_info, skb))
> +		goto out;
> +

Shouldn't you consume the 'skb' in case "not allowed"? the 'out' label
doesn't take care of that.

> +bool br_allowed_ingress(struct net_port_vlans *v, struct sk_buff *skb)
> +{
> +	struct net_port_vlan *pve;
> +	u16 vid;
> +
> +	/* If there are no vlan in the permitted list, all packets are
> +	 * permitted.
> +	 */
> +	if (list_empty(&v->vlan_list))
> +		return true;

Rethinking this, after discussed at [1].
The above means the port having no vlans is actually a member of every
possible vlan.
IMO it might not be what users expect, and may complicate things.

Maybe we should adapt a simpler approach:
If the bridge is a vlan enabled bridge, and the port is not a member of
the given vid, drop.
If the bridge is "vlan disabled", then all packets are permitted.

Regards,
Shmulik

[1]
http://marc.info/?l=linux-netdev&m=135602065425514&w=2