netdev - Re: [PATCH net RESEND] vlan: don't allow to add VLAN on VLAN device

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:	Fri, 28 Feb 2014 13:26:50 +0800
From:	Ding Tianhong <dingtianhong@...wei.com>
To:	John Fastabend <john.r.fastabend@...el.com>
CC:	Patrick McHardy <kaber@...sh.net>,
	"David S. Miller" <davem@...emloft.net>,
	Netdev <netdev@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH net RESEND] vlan: don't allow to add VLAN on VLAN device

On 2014/2/28 11:45, John Fastabend wrote:
> On 2/27/2014 6:43 PM, Ding Tianhong wrote:
>> I run these steps:
>>
>> modprobe 8021q
>> vconfig add eth2 20
>> vconfig add eth2.20 20
>> ifconfig eth2 xx.xx.xx.xx
>>
>> then the Call Trace happened:
>>
> 
> [...]
> 
>> ========================================================================
>>
>> The reason is that if add vlan on vlan dev, the vlan dev will create vlan_info,
>> then the notification will let the real dev to run dev_set_rx_mode() and hold
>> netif_addr_lock, and then the real dev will call ndo_set_rx_mode(), if the real
>> dev is vlan dev, the ndo_set_rx_mode() will hold netif_addr_lock again, so deadlock
>> happened.
>>
>> Don't allow to add vlan on vlan dev to fix this problem.
>>
>> Signed-off-by: Ding Tianhong <dingtianhong@...wei.com>
>> ---
> 
> I'm not sure we can just disable stacked vlans. There might be something
> using them today and they have worked in the past. Lets try to find a
> better fix.
> 
> .John

Yes, maybe I miss something, can you gave me a scene that the use of eth2.20.30?
the device is created from vlan device eth2.20, than I will find a better way to fix it.

Thanks
Ding

> -- 
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
> 
> 


--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html