[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <2252220.kyydmObEyQ@devil>
Date: Mon, 18 Mar 2013 16:36:40 +0100
From: Agostino Sarubbo <ago@...too.org>
To: oss-security@...ts.openwall.com
Subject: Re: CLONE_NEWUSER|CLONE_FS root exploit
On Wednesday 13 March 2013 18:33:00 Greg KH wrote:
> On Thu, Mar 14, 2013 at 09:03:20AM +0800, Eugene Teo wrote:
> > On 14 Mar, 2013, at 8:59 AM, Eugene Teo <eugeneteo@...nel.sg> wrote:
> > > On 13 Mar, 2013, at 11:39 PM, Sebastian Krahmer <krahmer@...e.de> wrote:
> > >> Hi,
> > >>
> > >> Seems like CLONE_NEWUSER|CLONE_FS might be a forbidden
> > >> combination.
> > >> During evaluating the new user namespace thingie, it turned out
> > >> that its trivially exploitable to get a (real) uid 0,
> > >> as demonstrated here:
> > >>
> > >> http://stealth.openwall.net/xSports/clown-newuser.c
> > >>
> > >> The trick is to setup a chroot in your CLONE_NEWUSER,
> > >> but also affecting the parent, which is running
> > >> in the init_user_ns, but with the chroot shared.
> > >> Then its trivial to get a rootshell from that.
> > >>
> > >> Tested on a openSUSE12.1 with a custom build 3.8.2 (x86_64).
> > >>
> > >> I hope I didnt make anything wrong, mixing up the UIDs,
> > >> or disabled important checks during kernel build on my test
> > >> system. ;)
> > >
> > > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?
> > > id=aea8b5d1e5c5482e7cdda849dc16d728f7080289>
> > I realised that the link is incorrect. Will post again when I see the
> > patches.
> It is commit e66eded8309ebf679d3d3c1f5820d1f2ca332c71 in Linus's tree,
> so replace the sha in the above link with this one instead.
Someone know exactly in which version the bug appears and which series are
affected?
--
Agostino Sarubbo
Gentoo Linux Developer
Powered by blists - more mailing lists
Please check out the
Open Source Software Security Wiki, which is counterpart to this
mailing list.
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
