linux-kernel - Re: [PATCH 11/11] blkcg: implement per-blkg request allocation

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: <20120427155612.GK10579@redhat.com>
Date:	Fri, 27 Apr 2012 11:56:12 -0400
From:	Vivek Goyal <vgoyal@...hat.com>
To:	Tejun Heo <tj@...nel.org>
Cc:	Jeff Moyer <jmoyer@...hat.com>, axboe@...nel.dk,
	ctalbott@...gle.com, rni@...gle.com, linux-kernel@...r.kernel.org,
	cgroups@...r.kernel.org, containers@...ts.linux-foundation.org,
	fengguang.wu@...el.com, hughd@...gle.com, akpm@...ux-foundation.org
Subject: Re: [PATCH 11/11] blkcg: implement per-blkg request allocation

On Fri, Apr 27, 2012 at 08:51:40AM -0700, Tejun Heo wrote:
> On Fri, Apr 27, 2012 at 11:48:41AM -0400, Vivek Goyal wrote:
> > Not an unpriviliged malicious application. In typical cgroup scenario, we
> > can allow unpriviliged users to create child cgroups so that it can
> > further subdivide its resources to its children group. (ex. put firefox
> > in one cgroup, open office in another group etc.).
> > 
> > So it is not same as jack up nr_requests.
> 
> I find allowing unpriv users creating cgroups dumb.  cgroup consumes
> kernel memory.  Sans using kmemcg, what prevents them from creating
> gazillion cgroups and consuming all memories?  The idea of allowing
> cgroups to !priv users is just broken from the get go.

Well creating a task consumes memory too but we allow unpriv users to
create tasks. :-)

May be a system wide cgroup limit will make sense?

Thanks
Vivek
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/