From: Seth Forshee <seth.forshee@canonical.com>
To: Andy Lutomirski <luto@amacapital.net>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
"Serge E. Hallyn" <serge@hallyn.com>,
Alexander Viro <viro@zeniv.linux.org.uk>,
Serge Hallyn <serge.hallyn@canonical.com>,
James Morris <james.l.morris@oracle.com>,
Linux FS Devel <linux-fsdevel@vger.kernel.org>,
LSM List <linux-security-module@vger.kernel.org>,
SELinux-NSA <selinux@tycho.nsa.gov>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 3/7] fs: Ignore file caps in mounts from other user namespaces
Date: Thu, 16 Jul 2015 08:06:07 -0500 [thread overview]
Message-ID: <20150716130607.GA77715@ubuntu-hedt> (raw)
In-Reply-To: <CALCETrUN-sK1gHPr5RxpGx5ZqXuYjJ6GiAxVW5kGM+fXTZKhgg@mail.gmail.com>
On Wed, Jul 15, 2015 at 06:23:01PM -0700, Andy Lutomirski wrote:
> > So if we have the s_user_ns check in get_file_caps the mnt_may_suid pass
> > isn't strictly necessary, but I still think it is useful as a mitigation
> > to the "leaks" Eric mentions. It _should_ be impossible for a user to
> > gain access to another user's mount namespace,
>
> No, it's very easy with SCM_RIGHTS. We should make sure it's safe.
Sure, what I really meant was that an attacker shouldn't be able to do
so without cooperation from the other user's processes. But I think
we're all in agreement that making it safe is a good idea.
Seth
next prev parent reply other threads:[~2015-07-16 13:06 UTC|newest]
Thread overview: 106+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-15 19:46 [PATCH 0/7] Initial support for user namespace owned mounts Seth Forshee
2015-07-15 19:46 ` [PATCH 1/7] fs: Add user namesapace member to struct super_block Seth Forshee
2015-07-16 2:47 ` Eric W. Biederman
2015-08-05 21:03 ` Seth Forshee
2015-08-05 21:19 ` Eric W. Biederman
2015-08-06 14:20 ` Seth Forshee
2015-08-06 14:51 ` Stephen Smalley
2015-08-06 15:44 ` Seth Forshee
2015-08-06 16:11 ` Stephen Smalley
2015-08-07 14:16 ` Seth Forshee
2015-08-07 14:32 ` Seth Forshee
2015-08-07 18:35 ` Casey Schaufler
2015-08-07 18:57 ` Seth Forshee
2015-07-15 19:46 ` [PATCH 2/7] userns: Simpilify MNT_NODEV handling Seth Forshee
2015-07-15 19:46 ` [PATCH 3/7] fs: Ignore file caps in mounts from other user namespaces Seth Forshee
2015-07-15 21:48 ` Serge E. Hallyn
2015-07-15 21:50 ` Andy Lutomirski
2015-07-15 22:35 ` Eric W. Biederman
2015-07-16 1:14 ` Seth Forshee
2015-07-16 1:23 ` Andy Lutomirski
2015-07-16 13:06 ` Seth Forshee [this message]
2015-07-16 1:19 ` Andy Lutomirski
2015-07-16 4:23 ` Eric W. Biederman
2015-07-16 4:49 ` Andy Lutomirski
2015-07-16 5:04 ` Eric W. Biederman
2015-07-16 5:15 ` Andy Lutomirski
2015-07-16 5:44 ` Eric W. Biederman
2015-07-16 13:13 ` Seth Forshee
2015-07-17 0:43 ` Eric W. Biederman
2015-07-29 16:04 ` Serge E. Hallyn
2015-07-29 16:18 ` Serge E. Hallyn
2015-07-15 19:46 ` [PATCH 4/7] fs: Treat foreign mounts as nosuid Seth Forshee
2015-07-17 6:46 ` Nikolay Borisov
2015-07-15 19:46 ` [PATCH 5/7] security: Restrict security attribute updates for userns mounts Seth Forshee
2015-07-15 19:46 ` [PATCH 6/7] selinux: Ignore security labels on user namespace mounts Seth Forshee
2015-07-16 13:23 ` Stephen Smalley
2015-07-22 16:02 ` Stephen Smalley
2015-07-22 16:14 ` Seth Forshee
2015-07-22 20:25 ` Stephen Smalley
2015-07-22 20:40 ` Stephen Smalley
2015-07-23 13:57 ` Stephen Smalley
2015-07-23 14:39 ` Seth Forshee
2015-07-23 15:36 ` Stephen Smalley
2015-07-23 16:23 ` Seth Forshee
2015-07-24 15:11 ` Seth Forshee
2015-07-30 15:57 ` Stephen Smalley
2015-07-30 16:24 ` Seth Forshee
2015-07-15 19:46 ` [PATCH 7/7] smack: Don't use security labels for " Seth Forshee
2015-07-15 20:43 ` Casey Schaufler
2015-07-15 20:36 ` [PATCH 0/7] Initial support for user namespace owned mounts Casey Schaufler
2015-07-15 21:06 ` Eric W. Biederman
2015-07-15 21:48 ` Seth Forshee
2015-07-15 22:28 ` Eric W. Biederman
2015-07-16 1:05 ` Andy Lutomirski
2015-07-16 2:20 ` Eric W. Biederman
2015-07-16 13:12 ` Stephen Smalley
2015-07-15 23:04 ` Casey Schaufler
2015-07-15 22:39 ` Casey Schaufler
2015-07-16 1:08 ` Andy Lutomirski
2015-07-16 2:54 ` Casey Schaufler
2015-07-16 4:47 ` Eric W. Biederman
2015-07-17 0:09 ` Dave Chinner
2015-07-17 0:42 ` Eric W. Biederman
2015-07-17 2:47 ` Dave Chinner
2015-07-21 17:37 ` J. Bruce Fields
2015-07-22 7:56 ` Dave Chinner
2015-07-22 14:09 ` J. Bruce Fields
2015-07-22 16:52 ` Austin S Hemmelgarn
2015-07-22 17:41 ` J. Bruce Fields
2015-07-23 1:51 ` Dave Chinner
2015-07-23 13:19 ` J. Bruce Fields
2015-07-23 23:48 ` Dave Chinner
2015-07-18 0:07 ` Serge E. Hallyn
2015-07-20 17:54 ` Colin Walters
2015-07-16 11:16 ` Lukasz Pawelczyk
2015-07-17 0:10 ` Eric W. Biederman
2015-07-17 10:13 ` Lukasz Pawelczyk
2015-07-16 3:15 ` Eric W. Biederman
2015-07-16 13:59 ` Seth Forshee
2015-07-16 15:09 ` Casey Schaufler
2015-07-16 18:57 ` Seth Forshee
2015-07-16 21:42 ` Casey Schaufler
2015-07-16 22:27 ` Andy Lutomirski
2015-07-16 23:08 ` Casey Schaufler
2015-07-16 23:29 ` Andy Lutomirski
2015-07-17 0:45 ` Casey Schaufler
2015-07-17 0:59 ` Andy Lutomirski
2015-07-17 14:28 ` Serge E. Hallyn
2015-07-17 14:56 ` Seth Forshee
2015-07-21 20:35 ` Seth Forshee
2015-07-22 1:52 ` Casey Schaufler
2015-07-22 15:56 ` Seth Forshee
2015-07-22 18:10 ` Casey Schaufler
2015-07-22 19:32 ` Seth Forshee
2015-07-23 0:05 ` Casey Schaufler
2015-07-23 0:15 ` Eric W. Biederman
2015-07-23 5:15 ` Seth Forshee
2015-07-23 21:48 ` Casey Schaufler
2015-07-28 20:40 ` Seth Forshee
2015-07-30 16:18 ` Casey Schaufler
2015-07-30 17:05 ` Eric W. Biederman
2015-07-30 17:25 ` Seth Forshee
2015-07-30 17:33 ` Eric W. Biederman
2015-07-17 13:21 ` Seth Forshee
2015-07-17 17:14 ` Casey Schaufler
2015-07-16 15:59 ` Seth Forshee
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