linux-kernel - Re: [PATCH 3/4] autofs4 - track uid and gid of last mount requestor

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]

Date:	Fri, 29 Feb 2008 19:20:09 +0300
From:	Pavel Emelyanov <xemul@...nvz.org>
To:	"Serge E. Hallyn" <serue@...ibm.com>
CC:	Ian Kent <raven@...maw.net>, Jeff Moyer <jmoyer@...hat.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Kernel Mailing List <linux-kernel@...r.kernel.org>,
	autofs mailing list <autofs@...ux.kernel.org>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	"Eric W. Biederman" <ebiederm@...ssion.com>
Subject: Re: [PATCH 3/4] autofs4 - track uid and gid of last mount requestor

> The way the user namespaces work right now is similar to say the IPC
> namespace - a task belongs to one user, that user belongs to precisely
> one user namespace.
> 
> Even in my additional userns patches, I was changing uid to store the
> (uid, userns) so a struct user still belonged to just one user
> namespace.
> 
> In contrast, with pid namespaces a task is associated with a 'struct
> pid' which links it to multiple process ids, one in each pid namespace
> to which it belongs.
> 
> Perhaps we should be treating user namespaces like pid namespaces?

I'm afraid, that I'm just starting a new thread of discussion in a
wrong place, but I can't refrain from asking "what for?"

> So if I'm user 500 in what I think is the initial user namespace, I can
> create a container with a new user namespace, the init task of which is
> both uid 0 in the child userns, and uid 500 in the higher level,
> automatically giving the container access to any files I own.

So do you mean that I can become a root, by calling clone()?

Thanks,
Pavel
--
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/