linux-kernel - Re: [RFC][v7][PATCH 0/9] Implement clone2() system call

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: <20090930053443.GA1010@x200>
Date:	Wed, 30 Sep 2009 09:34:43 +0400
From:	Alexey Dobriyan <adobriyan@...il.com>
To:	"Serge E. Hallyn" <serue@...ibm.com>
Cc:	Sukadev Bhattiprolu <sukadev@...ux.vnet.ibm.com>,
	linux-kernel@...r.kernel.org, Oren Laadan <orenl@...columbia.edu>,
	"Eric W. Biederman" <ebiederm@...ssion.com>,
	Pavel Emelyanov <xemul@...nvz.org>,
	Andrew Morton <akpm@...l.org>, torvalds@...ux-foundation.org,
	mikew@...gle.com, mingo@...e.hu, hpa@...or.com,
	Nathan Lynch <nathanl@...tin.ibm.com>, arnd@...db.de,
	peterz@...radead.org,
	Containers <containers@...ts.linux-foundation.org>,
	sukadev@...ibm.com
Subject: Re: [RFC][v7][PATCH 0/9] Implement clone2() system call

On Thu, Sep 24, 2009 at 01:35:56PM -0500, Serge E. Hallyn wrote:
> Quoting Alexey Dobriyan (adobriyan@...il.com):
> > I don't like this even more.
> > 
> > Pid namespaces are hierarchical _and_ anonymous, so simply
> > set of numbers doesn't describe the final object.
> > 
> > struct pid isn't special, it's just another invariant if you like
> > as far as C/R is concerned, but system call is made special wrt pids.
> > 
> > What will be in an image? I hope "struct kstate_image_pid" with several
> 
> Sure pid namespaces are anonymous, but we will give each an 'objref'
> valid only for a checkpoint image, and store the relationship between
> pid namespaces based on those objrefs.  Basically the same way that user
> structs and hierarchical user namespaces are handled right now.

OK, that's certainly doable.

You're commiting yourself to creation of tasks in userspace if this goes in. :-\
Which can let you into putting wrong kind of relations into image.
IIRC, clone_flags were in image (still?), but tomorrow kernel will get
new way to acquire, say, uts_ns, which, in theory, can't be described by
a set of consecutive clones, so, you'll have to fixup something in kernel.

> > numbers and with references to such object from other places, so it
> > seems natural to do alloc_pid() with needed numbers and that attach new
> > shiny pid to where needed. But this clone_pid is only for task_struct's pids.
--
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/