netdev - Re: [PATCH net-next] net-loopback: allow lo dev initial state to be controlled

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]

Message-ID: <eb1a89d2-f0c0-1c10-6588-c92939162713@6wind.com>
Date:   Thu, 19 Nov 2020 09:03:05 +0100
From:   Nicolas Dichtel <nicolas.dichtel@...nd.com>
To:     Mahesh Bandewar (महेश बंडेवार) <maheshb@...gle.com>
Cc:     David Ahern <dsahern@...il.com>, Ido Schimmel <idosch@...sch.org>,
        Jakub Kicinski <kuba@...nel.org>,
        Jian Yang <jianyang.kernel@...il.com>,
        David Miller <davem@...emloft.net>,
        linux-netdev <netdev@...r.kernel.org>,
        Jian Yang <jianyang@...gle.com>,
        Eric Dumazet <edumazet@...gle.com>
Subject: Re: [PATCH net-next] net-loopback: allow lo dev initial state to be
 controlled

Le 18/11/2020 à 18:39, Mahesh Bandewar (महेश बंडेवार) a écrit :
> On Wed, Nov 18, 2020 at 8:58 AM Nicolas Dichtel
> <nicolas.dichtel@...nd.com> wrote:
>>
>> Le 18/11/2020 à 02:12, David Ahern a écrit :
>> [snip]
>>> If there is no harm in just creating lo in the up state, why not just do
>>> it vs relying on a sysctl? It only affects 'local' networking so no real
>>> impact to containers that do not do networking (ie., packets can't
>>> escape). Linux has a lot of sysctl options; is this one really needed?
>>>
> I started with that approach but then I was informed about these
> containers that disable networking all together including loopback.
> Also bringing up by default would break backward compatibility hence
> resorted to sysctl.
>> +1
>>
>> And thus, it will benefit to everybody.
> 
> Well, it benefits everyone who uses networking (most of us) inside
Sure.

> netns but would create problems for workloads that create netns to
> disable networking. One can always disable it after creating the netns
> but that would mean change in the workflow and it could be viewed as
> regression.
The networking is very limited with only a loopback. Do you have some real use
case in mind?