From: ebiederm@xmission.com (Eric W. Biederman)
To: James Bottomley <James.Bottomley@Hansenpartnership.com>
Cc: Andrew Vagin <avagin@virtuozzo.com>,
Linux API <linux-api@vger.kernel.org>,
Containers <containers@lists.linux-foundation.org>,
lkml <linux-kernel@vger.kernel.org>,
criu@openvz.org,
"Michael Kerrisk \(man-pages\)" <mtk.manpages@gmail.com>
Subject: Re: [CRIU] Introspecting userns relationships to other namespaces?
Date: Fri, 08 Jul 2016 18:52:09 -0500 [thread overview]
Message-ID: <87wpkvpu1i.fsf@x220.int.ebiederm.org> (raw)
In-Reply-To: <5e4cc802-f0e0-4f4c-a2f7-585aaaa8feec@email.android.com> (James Bottomley's message of "Fri, 08 Jul 2016 15:19:28 -0700")
James Bottomley <James.Bottomley@Hansenpartnership.com> writes:
> On July 8, 2016 1:38:19 PM PDT, Andrew Vagin <avagin@virtuozzo.com> wrote:
>>What do you think about the idea to mount nsfs and be able to look up
>>any alive namespace by inum:
>
> I think I like it. It will give us a way to enter any extant
> namespace. It will work for Eric's fs namespaces as well. Perhaps a
> /process/ns/<inum> Directory?
*Shivers*
That makes it very easy to bypass any existing controls that exist for
getting at namespaces. It is true that everything of that kind is
directory based but still.
Plus I think it would serve as information leak to information outside
of the container.
An operation to get a user namespace file descriptor from some kernel
object sounds reasonably sane.
A great big list of things sounds about as scary as it can get. This is
not the time to be making it easier to escape from containers.
Eric
next prev parent reply other threads:[~2016-07-09 0:04 UTC|newest]
Thread overview: 46+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <c2a26220-69f2-f2f5-491a-e43abd9a6f92@gmail.com>
[not found] ` <87r3b7pxja.fsf@x220.int.ebiederm.org>
2016-07-06 8:41 ` Introspecting userns relationships to other namespaces? Michael Kerrisk (man-pages)
2016-07-06 14:13 ` Serge E. Hallyn
2016-07-06 15:46 ` Eric W. Biederman
2016-07-08 1:57 ` [CRIU] " Andrew Vagin
2016-07-08 7:44 ` Eric W. Biederman
2016-07-08 14:35 ` James Bottomley
2016-07-08 20:38 ` Andrew Vagin
2016-07-08 20:50 ` W. Trevor King
2016-07-08 22:19 ` James Bottomley
2016-07-08 22:19 ` James Bottomley
2016-07-08 23:52 ` Eric W. Biederman [this message]
2016-07-09 0:15 ` James Bottomley
2016-07-09 3:05 ` Eric W. Biederman
2016-07-09 7:26 ` Andrew Vagin
2016-07-09 10:31 ` James Bottomley
2016-07-09 10:32 ` James Bottomley
2016-07-09 18:15 ` Eric W. Biederman
2016-07-09 18:29 ` Eric W. Biederman
2016-07-13 0:08 ` Andrew Vagin
2016-07-13 3:59 ` W. Trevor King
2016-07-07 8:15 ` Michael Kerrisk (man-pages)
2016-07-07 13:36 ` Serge E. Hallyn
2016-07-07 15:01 ` James Bottomley
2016-07-07 18:21 ` Michael Kerrisk (man-pages)
2016-07-07 18:24 ` Serge E. Hallyn
2016-07-07 19:17 ` James Bottomley
2016-07-08 2:16 ` [CRIU] " Andrew Vagin
2016-07-08 3:00 ` Andrew Vagin
2016-07-08 3:26 ` James Bottomley
2016-07-08 5:26 ` W. Trevor King
2016-07-08 6:16 ` W. Trevor King
2016-07-08 6:54 ` Andrew Vagin
2016-07-08 7:18 ` W. Trevor King
2016-07-08 5:41 ` [CRIU] " Andrei Vagin
2016-07-08 5:47 ` Andrei Vagin
2016-07-08 6:07 ` James Bottomley
2016-07-08 11:17 ` Michael Kerrisk (man-pages)
2016-07-08 3:20 ` James Bottomley
2016-07-08 6:09 ` Andrew Vagin
2016-07-08 11:11 ` Michael Kerrisk (man-pages)
2016-07-09 3:15 ` W. Trevor King
2016-07-09 3:13 ` Eric W. Biederman
2016-07-10 5:36 ` [CRIU] " Andrew Vagin
2016-07-10 20:29 ` Eric W. Biederman
2016-07-10 21:06 ` James Bottomley
2016-07-11 20:55 ` Andrew Vagin
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=87wpkvpu1i.fsf@x220.int.ebiederm.org \
--to=ebiederm@xmission.com \
--cc=James.Bottomley@Hansenpartnership.com \
--cc=avagin@virtuozzo.com \
--cc=containers@lists.linux-foundation.org \
--cc=criu@openvz.org \
--cc=linux-api@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=mtk.manpages@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
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