From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH net-next] net: preserve sock reference when scrubbing the
 skb.
Date: Tue, 26 Jun 2018 19:35:17 -0700
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Cc: Flavio Leitner <fbl@redhat.com>,
        Linux Kernel Network Developers <netdev@vger.kernel.org>,
        Paolo Abeni <pabeni@redhat.com>,
        David Miller <davem@davemloft.net>,
        Florian Westphal <fw@strlen.de>,
        NetFilter <netfilter-devel@vger.kernel.org>
To: Cong Wang <xiyou.wangcong@gmail.com>,
        Eric Dumazet <eric.dumazet@gmail.com>
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On 06/26/2018 05:44 PM, Cong Wang wrote:
 
> With this, a netns could totally throttle a TCP socket in a different
> netns by holding the packets infinitely (e.g. putting them in a loop).
> This is where the isolation breaks.
> 

That is fine, really. Admin error -> Working as intended.

The current scrubbing is simply wrong, not documented, and added by someone
who had absolutely not intended all the side effects.