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From: "Serge E. Hallyn" <serue@us.ibm.com>
To: Oren Laadan <orenl@cs.columbia.edu>
Cc: Ingo Molnar <mingo@elte.hu>,
	containers@lists.osdl.org, Alexey Dobriyan <adobriyan@gmail.com>,
	Dave Hansen <dave@linux.vnet.ibm.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Linux-Kernel <linux-kernel@vger.kernel.org>
Subject: Re: Creating tasks on restart: userspace vs kernel
Date: Tue, 14 Apr 2009 11:16:01 -0500	[thread overview]
Message-ID: <20090414161601.GB8085@us.ibm.com> (raw)
In-Reply-To: <49E4A380.4070503@cs.columbia.edu>

Quoting Oren Laadan (orenl@cs.columbia.edu):
> For #1, we need to create a new container to begin with. This already
> requires CAP_SYS_ADMIN. Yes, for now we can use some setuid() to create
> a new pid_ns and then do the restart.

This is why I like tagging a pidns with a userid, and requiring that
current->euid==pidns->uid in order to be allowed to set pid in that
pidns.

We require cap_sys_admin wil doing clone(CLONE_NEWPID).  So if we do
that while uid=500, then drop cap_sys_admin, then we can proceed to
create new tasks with specified pids in that pidns.

-serge

  reply	other threads:[~2009-04-14 16:16 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-04-14  3:43 Creating tasks on restart: userspace vs kernel Oren Laadan
2009-04-14  9:59 ` Ingo Molnar
2009-04-14 14:53   ` Oren Laadan
2009-04-14 16:16     ` Serge E. Hallyn [this message]
2009-04-14 16:36 ` Alexey Dobriyan
2009-04-14 16:46   ` Alexey Dobriyan
     [not found]   ` <20090414163633.GE27461-2ev+ksY9ol182hYKe6nXyg@public.gmane.org>
2009-04-14 18:40     ` Oren Laadan
2009-04-14 19:59       ` Alexey Dobriyan
2009-04-14 20:10         ` Oren Laadan
2009-04-14 21:01           ` Alexey Dobriyan
2009-04-15 19:56       ` C/R without "leaks" (was: Re: Creating tasks on restart: userspace vs kernel) Alexey Dobriyan
2009-04-15 21:38         ` C/R without "leaks" Oren Laadan
2009-04-22  0:16           ` Nathan Lynch
2009-04-15 22:42         ` C/R without "leaks" (was: Re: Creating tasks on restart: userspace vs kernel) Greg Kurz
2009-04-16 16:12           ` Alexey Dobriyan
2009-04-16 18:10             ` C/R without "leaks" Chris Friesen
     [not found]               ` <49E774B1.5060505-ZIRUuHA3oDzQT0dZR+AlfA@public.gmane.org>
2009-04-16 18:39                 ` Oren Laadan
2009-04-17  9:15                   ` Greg Kurz
2009-04-17  9:48                     ` Oren Laadan
2009-04-17 12:25                       ` Greg Kurz
2009-04-17  8:46             ` C/R without "leaks" (was: Re: Creating tasks on restart: userspace vs kernel) Greg Kurz

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