From: ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org (Eric W. Biederman)
To: Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Cc: containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org,
Aristeu Rozanski <aris-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>,
cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Subject: Re: Why does devices cgroup check for CAP_SYS_ADMIN explicitly?
Date: Tue, 06 Nov 2012 03:58:04 -0800 [thread overview]
Message-ID: <877gpzrlir.fsf@xmission.com> (raw)
In-Reply-To: <20121106023845.GI19354-9pTldWuhBndy/B6EtB590w@public.gmane.org> (Tejun Heo's message of "Mon, 5 Nov 2012 18:38:45 -0800")
Tejun Heo <tj-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> writes:
> Hello, guys.
>
> Why doesn't it follow the usual security enforced by cgroupfs
> permissions? Why is the explicit check necessary?
An almost more interesting question is why is cgroup one of the last
pieces of code not using capabilities and instead lets you attach to any
process simply if your uid == 0.
I don't know the history but the device cgroup testing for CAP_SYS_ADMIN
makes a naive sort of sense to me.
Eric
next parent reply other threads:[~2012-11-06 11:58 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20121106023845.GI19354@mtj.dyndns.org>
[not found] ` <20121106023845.GI19354-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 11:58 ` Eric W. Biederman [this message]
[not found] ` <877gpzrlir.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2012-11-06 14:48 ` Why does devices cgroup check for CAP_SYS_ADMIN explicitly? Tejun Heo
2012-11-06 15:01 ` Serge Hallyn
[not found] ` <20121106150131.GA14640@sergelap>
2012-11-06 15:06 ` Tejun Heo
[not found] ` <20121106150639.GB30069@mtj.dyndns.org>
[not found] ` <20121106150639.GB30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 15:30 ` Serge Hallyn
2012-11-06 15:34 ` Eric W. Biederman
[not found] ` <20121106153032.GB18218@sergelap>
2012-11-06 15:41 ` Tejun Heo
[not found] ` <20121106154105.GD30069@mtj.dyndns.org>
[not found] ` <20121106154105.GD30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 16:12 ` Aristeu Rozanski
[not found] ` <871ug6rbio.fsf@xmission.com>
[not found] ` <871ug6rbio.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2012-11-06 15:43 ` Tejun Heo
[not found] ` <20121106154320.GE30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 16:10 ` Eric W. Biederman
[not found] ` <87sj8mogpp.fsf@xmission.com>
[not found] ` <87sj8mogpp.fsf-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>
2012-11-06 16:52 ` Tejun Heo
[not found] ` <20121106165246.GF30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 17:31 ` Serge Hallyn
[not found] ` <20121106173104.GA27990@sergelap>
2012-11-06 17:38 ` Tejun Heo
[not found] ` <20121106173823.GK30069@mtj.dyndns.org>
[not found] ` <20121106173823.GK30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 17:41 ` Tejun Heo
[not found] ` <20121106174130.GL30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 18:02 ` Serge Hallyn
[not found] ` <20121106180233.GA31008@sergelap>
2012-11-06 18:08 ` Tejun Heo
2012-11-06 18:12 ` Serge Hallyn
[not found] ` <20121106181214.GB31008@sergelap>
2012-11-06 18:16 ` Tejun Heo
[not found] ` <20121106181623.GO30069@mtj.dyndns.org>
[not found] ` <20121106181623.GO30069-9pTldWuhBndy/B6EtB590w@public.gmane.org>
2012-11-06 18:25 ` Serge Hallyn
2012-11-06 15:45 ` Serge Hallyn
2012-11-06 2:38 Tejun Heo
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