From: ebiederm@xmission•com (Eric W. Biederman)
To: canqun zhang <canqunzhang@gmail•com>
Cc: Gao feng <gaofeng@cn•fujitsu.com>,
netfilter-devel@vger•kernel.org,
"netdev\@vger.kernel.org" <netdev@vger•kernel.org>,
Patrick McHardy <kaber@trash•net>,
pablo@netfilter•org
Subject: Re: [PATCH 01/19] netfilter: move nf_conntrack initialize out of pernet operations
Date: Thu, 27 Dec 2012 22:00:23 -0800 [thread overview]
Message-ID: <8738yqiumg.fsf@xmission.com> (raw)
In-Reply-To: <CAFFEFTU8kxXV2pQ3B_goRs2Y7p2ecZ1YuSKSjfYF_58eD1tDqw@mail.gmail.com> (canqun zhang's message of "Fri, 28 Dec 2012 13:32:29 +0800")
canqun zhang <canqunzhang@gmail•com> writes:
> yes，Network namespaces in general can be cleaned up in any order，but
> when doing /etc/ini.d/iptables restart, the system need cleaning up
> all net namespace,and init_net should be cleanup lastly.init_net is
> the first namespace,other net namespace is copied for it ,and it is
> diuty for Initializing resources,so It in itself is special.
"other net namespaces is copied for it" I don't have a clue what
you mean by that. Every network namespace starts out in a default
state not in a copied state.
Nowhere else in the network stack does &init_net have the duty
of initializing or cleaning up resources.
That /etc/init.d/iptables restart removes modules in general is a little
dubious. That /etc/init.d/iptables restart removes modules when there
are other existing network namespaces using those modules is down right
dangerous. Dangerous in the anyone can ssh into the machine way. I
suspect it has taken 5 years for this bug to show up because it is so
idiotic to remove code that someone else is using.
I won't argue that making it so that &init_net is the last network
namespace to go will solve this problem. But I can't see how adding
the guarantee that &init_net will always be cleaned up last is a good
long term solution.
Removing the init_net special case gives a simpler mental model, and
less to learn and maintain about network namespaces.
Eric
--
To unsubscribe from this list: send the line "unsubscribe netfilter-devel" in
the body of a message to majordomo@vger•kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
next prev parent reply other threads:[~2012-12-28 6:00 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-12-28 2:36 [PATCH 01/19] netfilter: move nf_conntrack initialize out of pernet operations Gao feng
2012-12-28 2:36 ` [PATCH 02/19] netfilter: expect: move initial codes out of pernet_operations Gao feng
2012-12-28 2:36 ` [PATCH 03/19] netfilter: acct: " Gao feng
2012-12-28 2:36 ` [PATCH 04/19] netfilter: tstamp: " Gao feng
2012-12-28 2:36 ` [PATCH 05/19] netfilter: ecache: " Gao feng
2012-12-28 2:36 ` [PATCH 06/19] netfilter: timeout: " Gao feng
2012-12-28 2:36 ` [PATCH 07/19] netfilter: helper: " Gao feng
2012-12-28 2:36 ` [PATCH 08/19] netfilter: proto: " Gao feng
2012-12-28 2:36 ` [PATCH 09/19] netfilter: l3proto: prepare reworking l3proto support for netns Gao feng
2012-12-28 2:36 ` [PATCH 10/19] netfilter: ipv4: register ipv4 in module_init Gao feng
2012-12-28 2:36 ` [PATCH 10/19] netfilter: ipv4: register l3proto " Gao feng
2012-12-28 2:36 ` [PATCH 11/19] netfilter: ipv6: register l3proto ipv6 " Gao feng
2012-12-28 2:36 ` [PATCH 12/19] netfilter: l4proto: prepare reworking l4proto support for netns Gao feng
2012-12-28 2:36 ` [PATCH 13/19] netfilter: ipv4: move registration codes out of pernet_operations Gao feng
2012-12-28 2:36 ` [PATCH 14/19] netfilter: ipv6: " Gao feng
2012-12-28 2:36 ` [PATCH 15/19] netfilter: sctp: " Gao feng
2012-12-28 2:36 ` [PATCH 16/19] netfilter: udplite: " Gao feng
2012-12-28 2:36 ` [PATCH 17/19] netfilter: dccp: " Gao feng
2012-12-28 2:36 ` [PATCH 18/19] netfilter: gre: " Gao feng
2012-12-28 2:36 ` [PATCH 19/19] netfilter: gre: fix resource leak when unregister gre proto Gao feng
2013-01-05 3:50 ` Pablo Neira Ayuso
2013-01-07 1:27 ` Gao feng
2013-01-07 2:15 ` Pablo Neira Ayuso
2013-01-07 2:38 ` Pablo Neira Ayuso
2013-01-07 2:59 ` Gao feng
2013-01-07 3:05 ` Gao feng
2013-01-07 3:27 ` Pablo Neira Ayuso
2013-01-07 3:43 ` Gao feng
2012-12-28 3:52 ` [PATCH 01/19] netfilter: move nf_conntrack initialize out of pernet operations canqun zhang
2012-12-28 4:48 ` Eric W. Biederman
2012-12-28 5:32 ` canqun zhang
2012-12-28 6:00 ` Eric W. Biederman [this message]
2012-12-28 11:58 ` Pablo Neira Ayuso
2012-12-28 7:16 ` Gao feng
2012-12-28 8:48 ` canqun zhang
2013-01-10 1:03 ` Gao feng
2013-01-10 16:41 ` Pablo Neira Ayuso
2013-01-11 1:01 ` Gao feng
2013-01-13 15:07 ` Pablo Neira Ayuso
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=8738yqiumg.fsf@xmission.com \
--to=ebiederm@xmission$(echo .)com \
--cc=canqunzhang@gmail$(echo .)com \
--cc=gaofeng@cn$(echo .)fujitsu.com \
--cc=kaber@trash$(echo .)net \
--cc=netdev@vger$(echo .)kernel.org \
--cc=netfilter-devel@vger$(echo .)kernel.org \
--cc=pablo@netfilter$(echo .)org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox