Re: [PATCH net-next 3/6] net: 8021q: vlan_dev: add vid tag for vlan device own address

[Florian Fainelli <f.fainelli@gmail.com>]

On 2/26/2019 10:45 AM, Ivan Khoronzhuk wrote:
> The vlan device address is held separately from uc/mc lists and
> handled differently. The vlan dev address is bound with real device
> address only if it's inherited from init, in all other cases it's
> separate address entry in uc list. With vid set, the address becomes
> not inherited from real device after it's set manually as before, but
> is part of uc list any way, with appropriate vid tag set. If vid_len
> for real device is 0, the behaviour is the same as before this change,
> so shouldn't be any impact on systems w/o individual virtual device
> filtering (IVDF) enabled. This allows to control and sync vlan device
> address and disable concrete vlan packet income when vlan interface is
> down.
> 
> Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@linaro.org>
> ---

[snip]

>  
> +static int vlan_dev_add_addr(struct net_device *dev, u8 *addr)
> +{
> +	struct net_device *real_dev = vlan_dev_real_dev(dev);
> +	unsigned char naddr[ETH_ALEN + NET_8021Q_VID_TSIZE];
> +
> +	if (real_dev->vid_len) {

Don't you need to check that real_dev->vid_len is >= NET_8021Q_VID_TSIZE
here?

> +		memcpy(naddr, addr, dev->addr_len);
> +		vlan_dev_set_addr_vid(dev, naddr);
> +		return dev_vid_uc_add(real_dev, naddr);
> +	}
> +
> +	if (ether_addr_equal(addr, real_dev->dev_addr))
> +		return 0;
> +
> +	return dev_uc_add(real_dev, addr);
> +}
> +
> +static void vlan_dev_del_addr(struct net_device *dev, u8 *addr)
> +{
> +	struct net_device *real_dev = vlan_dev_real_dev(dev);
> +	unsigned char naddr[ETH_ALEN + NET_8021Q_VID_TSIZE];
> +
> +	if (real_dev->vid_len) {

Same here.

> +		memcpy(naddr, addr, dev->addr_len);
> +		vlan_dev_set_addr_vid(dev, naddr);
> +		dev_vid_uc_del(real_dev, naddr);
> +		return;
> +	}
> +
> +	if (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr))
> +		dev_uc_del(real_dev, addr);
> +}
> +
> +static int vlan_dev_subs_addr(struct net_device *dev, u8 *addr)
> +{
> +	int err;
> +
> +	err = vlan_dev_add_addr(dev, addr);
> +	if (err < 0)
> +		return err;
> +
> +	vlan_dev_del_addr(dev, dev->dev_addr);
> +	return err;
> +}
> +
>  bool vlan_dev_inherit_address(struct net_device *dev,
>  			      struct net_device *real_dev)
>  {
>  	if (dev->addr_assign_type != NET_ADDR_STOLEN)
>  		return false;
>  
> +	if (real_dev->vid_len)
> +		if (vlan_dev_subs_addr(dev, real_dev->dev_addr))
> +			return false;

The check on real_dev->vid_len can be absorbed into vlan_dev_subs_addr()?

> +
>  	ether_addr_copy(dev->dev_addr, real_dev->dev_addr);
>  	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
>  	return true;
> @@ -278,9 +327,10 @@ static int vlan_dev_open(struct net_device *dev)
>  	    !(vlan->flags & VLAN_FLAG_LOOSE_BINDING))
>  		return -ENETDOWN;
>  
> -	if (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr) &&
> -	    !vlan_dev_inherit_address(dev, real_dev)) {
> -		err = dev_uc_add(real_dev, dev->dev_addr);
> +	if (ether_addr_equal(dev->dev_addr, real_dev->dev_addr) ||
> +	    (!ether_addr_equal(dev->dev_addr, real_dev->dev_addr) &&
> +	     !vlan_dev_inherit_address(dev, real_dev))) {

Should this condition simply become if !vlan_dev_inherit_address() now?
-- 
Florian