From: Josh Triplett <josh@joshtriplett.org>
To: "Kirill A. Shutemov" <kirill@shutemov.name>
Cc: David Herrmann <dh.herrmann@gmail.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
Andy Lutomirski <luto@amacapital.net>,
Jiri Kosina <jikos@kernel.org>, Greg KH <greg@kroah.com>,
Hannes Reinecke <hare@suse.com>,
Steven Rostedt <rostedt@goodmis.org>,
Arnd Bergmann <arnd@arndb.de>, Tom Gundersen <teg@jklm.no>,
Andrew Morton <akpm@linux-foundation.org>
Subject: Re: [RFC v1 00/14] Bus1 Kernel Message Bus
Date: Sat, 29 Oct 2016 14:04:37 -0700 [thread overview]
Message-ID: <20161029210437.la5opn65xxsdlrvb@x> (raw)
In-Reply-To: <20161027004524.GA4184@node>
On Thu, Oct 27, 2016 at 03:45:24AM +0300, Kirill A. Shutemov wrote:
> On Wed, Oct 26, 2016 at 10:34:30PM +0200, David Herrmann wrote:
> > Long story short: We have uid<->uid quotas so far, which prevent DoS
> > attacks, unless you get access to a ridiculous amount of local UIDs.
> > Details on which resources are accounted can be found in the wiki [1].
>
> Does only root user_ns uid count as separate or per-ns too?
>
> In first case we will have vitually unbounded access to UIDs.
>
> The second case can cap number of user namespaces a user can create while
> using bus1 inside.
That seems easy enough to solve. Make the uid<->uid quota use uids in
the namespace of the side whose resources the operation uses. That way,
if both sender and recipient live in a user namespace then you get quota
per user in the namespace, but you can't use a user namespace to cheat
and manufacture more users to get more quota when talking to something
*outside* that namespace.
- Josh Triplett
next prev parent reply other threads:[~2016-10-29 21:06 UTC|newest]
Thread overview: 55+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-10-26 19:17 [RFC v1 00/14] Bus1 Kernel Message Bus David Herrmann
2016-10-26 19:17 ` [RFC v1 01/14] bus1: add bus1(7) man-page David Herrmann
2016-10-27 23:12 ` Kirill A. Shutemov
2016-10-26 19:17 ` [RFC v1 02/14] bus1: provide stub cdev /dev/bus1 David Herrmann
2016-10-26 23:19 ` Andy Lutomirski
2016-10-26 23:54 ` Tom Gundersen
2016-10-27 9:11 ` Arnd Bergmann
2016-10-27 15:25 ` Tom Gundersen
2016-10-27 16:37 ` Linus Torvalds
2016-10-27 16:39 ` Tom Gundersen
2016-10-29 22:13 ` Arnd Bergmann
2016-10-26 19:17 ` [RFC v1 03/14] bus1: util - active reference utility library David Herrmann
2016-10-26 19:18 ` [RFC v1 04/14] bus1: util - fixed list " David Herrmann
2016-10-27 12:37 ` Peter Zijlstra
2016-10-27 12:48 ` David Herrmann
2016-10-27 12:56 ` Arnd Bergmann
2016-10-27 13:31 ` David Herrmann
2016-10-26 19:18 ` [RFC v1 05/14] bus1: util - pool " David Herrmann
2016-10-27 12:54 ` Peter Zijlstra
2016-10-27 12:59 ` Peter Zijlstra
2016-10-27 15:00 ` Peter Zijlstra
2016-10-27 15:14 ` Peter Zijlstra
2016-10-26 19:18 ` [RFC v1 06/14] bus1: util - queue " David Herrmann
2016-10-27 15:27 ` Peter Zijlstra
2016-10-27 16:43 ` Peter Zijlstra
2016-10-28 11:33 ` Tom Gundersen
2016-10-28 13:33 ` Peter Zijlstra
2016-10-28 13:47 ` Tom Gundersen
2016-10-28 13:58 ` Peter Zijlstra
2016-10-28 14:33 ` Tom Gundersen
2016-10-28 16:49 ` Peter Zijlstra
2016-10-26 19:18 ` [RFC v1 07/14] bus1: tracking user contexts David Herrmann
2016-10-26 19:18 ` [RFC v1 08/14] bus1: implement peer management context David Herrmann
2016-10-28 12:06 ` Richard Weinberger
2016-10-28 13:18 ` Tom Gundersen
2016-10-28 13:21 ` Richard Weinberger
2016-10-28 13:05 ` Richard Weinberger
2016-10-28 13:23 ` Tom Gundersen
2016-10-28 13:54 ` Richard Weinberger
2016-10-26 19:18 ` [RFC v1 09/14] bus1: provide transaction context for multicasts David Herrmann
2016-10-28 14:37 ` Peter Zijlstra
2016-10-26 19:18 ` [RFC v1 10/14] bus1: add handle management David Herrmann
2016-10-26 19:18 ` [RFC v1 11/14] bus1: implement message transmission David Herrmann
2016-10-26 19:18 ` [RFC v1 12/14] bus1: hook up file-operations David Herrmann
2016-10-26 19:18 ` [RFC v1 13/14] bus1: limit and protect resources David Herrmann
2016-10-26 19:18 ` [RFC v1 14/14] bus1: basic user-space kselftests David Herrmann
2016-10-26 19:39 ` [RFC v1 00/14] Bus1 Kernel Message Bus Linus Torvalds
2016-10-26 20:34 ` David Herrmann
2016-10-27 0:45 ` Kirill A. Shutemov
2016-10-29 21:04 ` Josh Triplett [this message]
2016-11-02 14:45 ` David Herrmann
2017-01-30 22:11 ` Pavel Machek
2016-10-27 11:10 ` Michael Kerrisk
2016-10-28 13:11 ` Richard Weinberger
2016-10-28 13:37 ` Tom Gundersen
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