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:   Tue, 14 May 2019 09:32:32 +0200
From:   Nicolas Dichtel <>
To:     Sabrina Dubroca <>
Cc:, Dan Winship <>
Subject: Re: [PATCH net v2] rtnetlink: always put ILFA_LINK for links with a

Le 13/05/2019 à 23:46, Sabrina Dubroca a écrit :
> 2019-05-13, 17:13:36 +0200, Nicolas Dichtel wrote:
>> Le 13/05/2019 à 17:08, Sabrina Dubroca a écrit :
>>> 2019-05-13, 16:50:51 +0200, Nicolas Dichtel wrote:
>>>> Le 13/05/2019 à 15:47, Sabrina Dubroca a écrit :
>>>>> Currently, nla_put_iflink() doesn't put the IFLA_LINK attribute when
>>>>> iflink == ifindex.
>>>>> In some cases, a device can be created in a different netns with the
>>>>> same ifindex as its parent. That device will not dump its IFLA_LINK
>>>>> attribute, which can confuse some userspace software that expects it.
>>>>> For example, if the last ifindex created in init_net and foo are both
>>>>> 8, these commands will trigger the issue:
>>>>>     ip link add parent type dummy                   # ifindex 9
>>>>>     ip link add link parent netns foo type macvlan  # ifindex 9 in ns foo
>>>>> So, in case a device puts the IFLA_LINK_NETNSID attribute in a dump,
>>>>> always put the IFLA_LINK attribute as well.
>>>>> Thanks to Dan Winship for analyzing the original OpenShift bug down to
>>>>> the missing netlink attribute.
>>>>> Analyzed-by: Dan Winship <>
>>>>> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
>>>> I would say:
>>>> Fixes: 5e6700b3bf98 ("sit: add support of x-netns")
>>>> Because before this patch, there was no device with an iflink that can be put in
>>>> another netns.
>>> That tells us how far back we might want to backport this fix, but not
>>> which commit introduced the bug. I think Fixes should refer to the
>>> introduction of the faulty code, not to what patch made it visible (if
>>> we can find both).
>> No sure to follow you. The problem you describe cannot happen before commit
>> 5e6700b3bf98, so there cannot be a "faulty" patch before that commit.
> What about macvlan devices?
> From commit b863ceb7ddce ("[NET]: Add macvlan driver"):
> static int macvlan_init(struct net_device *dev)
> {
> ...
>         dev->iflink             = lowerdev->ifindex;
> ...
> }
> vlan devices also had an iflink assigned since commit ddd7bf9fe4e5.
> What am I missing?
You miss the fact that netns have been introduced after both commits.

What about this one?
Fixes: d8a5ec672768 ("[NET]: netlink support for moving devices between network


Powered by blists - more mailing lists