From: ebiederm@xmission.com (Eric W. Biederman)
To: Kees Cook <keescook@chromium.org>
Cc: Sebastian Krahmer <krahmer@suse.de>,
linux-kernel@vger.kernel.org, Oleg Nesterov <oleg@redhat.com>,
Linux Containers <containers@lists.linux-foundation.org>
Subject: Re: CLONE_NEWUSER|CLONE_FS root exploit
Date: Wed, 13 Mar 2013 11:35:15 -0700 [thread overview]
Message-ID: <87r4jjkv18.fsf@xmission.com> (raw)
In-Reply-To: <20130313175729.GH12501@outflux.net> (Kees Cook's message of "Wed, 13 Mar 2013 10:57:29 -0700")
Kees Cook <keescook@chromium.org> writes:
> Hi,
>
> It seem like we should block (at least) this combination. On 3.9, this
> exploit works once uidmapping is added.
>
> http://www.openwall.com/lists/oss-security/2013/03/13/10
Yes. That is a bad combination. It let's chroot confuse privileged
processes.
Now to figure out if this is easier to squash by adding a user_namespace
to fs_struct or by just forbidding this combination.
Eric
next prev parent reply other threads:[~2013-03-13 18:35 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-13 17:57 CLONE_NEWUSER|CLONE_FS root exploit Kees Cook
2013-03-13 18:35 ` Eric W. Biederman [this message]
2013-03-14 1:48 ` Andy Lutomirski
2013-03-14 20:29 ` Eric W. Biederman
2013-03-14 21:32 ` Andy Lutomirski
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=87r4jjkv18.fsf@xmission.com \
--to=ebiederm@xmission.com \
--cc=containers@lists.linux-foundation.org \
--cc=keescook@chromium.org \
--cc=krahmer@suse.de \
--cc=linux-kernel@vger.kernel.org \
--cc=oleg@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox