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Message-ID: <5423D808.7050800@6wind.com>
Date: Thu, 25 Sep 2014 10:53:28 +0200
From: Nicolas Dichtel <nicolas.dichtel@6wind.com>
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To: Cong Wang <cwang@twopensource.com>
CC: netdev <netdev@vger.kernel.org>, containers@lists.linux-foundation.org,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        linux-api@vger.kernel.org, David Miller <davem@davemloft.net>,
        "Eric W. Biederman" <ebiederm@xmission.com>,
        Stephen Hemminger <stephen@networkplumber.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Andy Lutomirski <luto@amacapital.net>
Subject: Re: [RFC PATCH net-next v2 0/5] netns: allow to identify peer netns
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Le 24/09/2014 18:48, Cong Wang a écrit :
> On Wed, Sep 24, 2014 at 9:31 AM, Nicolas Dichtel
> <nicolas.dichtel@6wind.com> wrote:
>>> I think in this case your ID's are still available, but aren't you
>>> providing a new way
>>> for the inner netns device to escape which we are trying to avoid?
>>
>> It's why the ids depend on user ns. Only if user ns are the same we allow to
>> get an id for a peer netns.
>
> Too late, userns is relatively new, relying on it breaks our existing
> assumption.
>
I don't get your point. netns has been added in kernel after user ns:
acce292c82d4 user namespace: add the framework => 2.6.23
5f256becd868 [NET]: Basic network namespace infrastructure. => 2.6.24

In the kernel, each netns is linked with a user ns.