Subject: Re: [PATCH net-next 1/2] vlan: don't allow vlan device to move between network namespaces

From: Ding Tianhong <[email-masked]>
Date: Fri, 28 Feb 2014 16:52:29 +0800

On 2014/2/28 16:12, Toshiaki Makita wrote:
> (2014/02/28 16:50), Ding Tianhong wrote:
>> Now the vlan device could move to another network namespace, but
>> the read dev is sill in the old network namespace, it is unsafe
>> and the vlan device could not work well, so don't allow to do it.
> 
> Why is this a problem?
> This looks like a useful feature to me.
> 
> Thanks,
> Toshiaki Makita
> 
I think the vlan dev is a virtual device, if it does not with real dev together,
I am not sure whether it is correct. Maybe I miss something, pls remind me.

Thanks
Ding

>>
>> Signed-off-by: Ding Tianhong <[email-masked]>
>> ---
>>  net/8021q/vlan_dev.c | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/net/8021q/vlan_dev.c b/net/8021q/vlan_dev.c
>> index 566adbf..76d8fab 100644
>> --- a/net/8021q/vlan_dev.c
>> +++ b/net/8021q/vlan_dev.c
>> @@ -791,5 +791,8 @@ void vlan_setup(struct net_device *dev)
>>  	dev->destructor		= free_netdev;
>>  	dev->ethtool_ops	= &vlan_ethtool_ops;
>>  
>> +	/* don't allow vlan device to move between network namespaces */
>> +	dev->features		|= NETIF_F_NETNS_LOCAL;
>> +
>>  	memset(dev->broadcast, 0, ETH_ALEN);
>>  }
>>
> 
>