From: Andy Lutomirski <luto@kernel.org>
To: Christian Brauner <christian.brauner@ubuntu.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>,
"Stéphane Graber" <stgraber@ubuntu.com>,
"Eric W. Biederman" <ebiederm@xmission.com>,
"Aleksa Sarai" <cyphar@cyphar.com>,
"Jann Horn" <jannh@google.com>,
smbarber@chromium.org,
"Seth Forshee" <seth.forshee@canonical.com>,
"Alexander Viro" <viro@zeniv.linux.org.uk>,
"Alexey Dobriyan" <adobriyan@gmail.com>,
"James Morris" <jmorris@namei.org>,
"Kees Cook" <keescook@chromium.org>,
"Jonathan Corbet" <corbet@lwn.net>,
"Phil Estes" <estesp@gmail.com>,
LKML <linux-kernel@vger.kernel.org>,
"Linux FS Devel" <linux-fsdevel@vger.kernel.org>,
"Linux Containers" <containers@lists.linux-foundation.org>,
"LSM List" <linux-security-module@vger.kernel.org>,
"Linux API" <linux-api@vger.kernel.org>
Subject: Re: [PATCH v3 09/25] fs: add is_userns_visible() helper
Date: Wed, 19 Feb 2020 09:18:51 -0800 [thread overview]
Message-ID: <CALCETrW-XPkBMs30vk+Aiv+jA5i7TjHOYCgz0Ud6d0geaYte=g@mail.gmail.com> (raw)
In-Reply-To: <20200219120604.vqudwaeppebvisco@wittgenstein>
On Wed, Feb 19, 2020 at 4:06 AM Christian Brauner
<christian.brauner@ubuntu.com> wrote:
>
> On Tue, Feb 18, 2020 at 08:42:33PM -0600, Serge Hallyn wrote:
> > On Tue, Feb 18, 2020 at 03:33:55PM +0100, Christian Brauner wrote:
> > > Introduce a helper which makes it possible to detect fileystems whose
> > > superblock is visible in multiple user namespace. This currently only
> > > means proc and sys. Such filesystems usually have special semantics so their
> > > behavior will not be changed with the introduction of fsid mappings.
> >
> > Hi,
> >
> > I'm afraid I've got a bit of a hangup about the terminology here. I
> > *think* what you mean is that SB_I_USERNS_VISIBLE is an fs whose uids are
> > always translated per the id mappings, not fsid mappings. But when I see
>
> Correct!
>
> > the name it seems to imply that !SB_I_USERNS_VISIBLE filesystems can't
> > be seen by other namespaces at all.
> >
> > Am I right in my first interpretation? If so, can we talk about the
> > naming?
>
> Yep, your first interpretation is right. What about: wants_idmaps()
Maybe fsidmap_exempt()?
I still haven't convinced myself that any of the above is actually
correct behavior, especially when people do things like creating
setuid binaries.
next prev parent reply other threads:[~2020-02-19 17:19 UTC|newest]
Thread overview: 51+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-02-18 14:33 [PATCH v3 00/25] user_namespace: introduce fsid mappings Christian Brauner
2020-02-18 14:33 ` [PATCH v3 01/25] user_namespace: introduce fsid mappings infrastructure Christian Brauner
2020-02-19 2:33 ` Serge E. Hallyn
2020-02-18 14:33 ` [PATCH v3 02/25] proc: add /proc/<pid>/fsuid_map Christian Brauner
2020-02-19 2:33 ` Serge E. Hallyn
2020-02-18 14:33 ` [PATCH v3 03/25] proc: add /proc/<pid>/fsgid_map Christian Brauner
2020-02-19 2:33 ` Serge E. Hallyn
2020-02-18 14:33 ` [PATCH v3 04/25] fsuidgid: add fsid mapping helpers Christian Brauner
2020-02-18 14:33 ` [PATCH v3 05/25] user_namespace: refactor map_write() Christian Brauner
2020-02-19 2:35 ` Serge E. Hallyn
2020-02-18 14:33 ` [PATCH v3 06/25] user_namespace: make map_write() support fsid mappings Christian Brauner
2020-02-19 16:18 ` Jann Horn
2020-02-18 14:33 ` [PATCH v3 07/25] proc: task_state(): use from_kfs{g,u}id_munged Christian Brauner
2020-02-19 2:36 ` Serge E. Hallyn
2020-02-18 14:33 ` [PATCH v3 08/25] cred: add kfs{g,u}id Christian Brauner
2020-02-18 14:33 ` [PATCH v3 09/25] fs: add is_userns_visible() helper Christian Brauner
2020-02-19 2:42 ` Serge E. Hallyn
2020-02-19 12:06 ` Christian Brauner
2020-02-19 17:18 ` Andy Lutomirski [this message]
2020-02-20 14:26 ` Serge E. Hallyn
2020-02-18 14:33 ` [PATCH v3 10/25] namei: may_{o_}create(): handle fsid mappings Christian Brauner
2020-02-18 14:33 ` [PATCH v3 11/25] inode: inode_owner_or_capable(): " Christian Brauner
2020-02-18 22:25 ` Christoph Hellwig
2020-02-19 12:29 ` Christian Brauner
2020-02-18 14:33 ` [PATCH v3 12/25] capability: privileged_wrt_inode_uidgid(): " Christian Brauner
2020-02-18 14:33 ` [PATCH v3 13/25] stat: " Christian Brauner
2020-02-18 14:34 ` [PATCH v3 14/25] open: " Christian Brauner
2020-02-18 14:34 ` [PATCH v3 15/25] posix_acl: " Christian Brauner
2020-02-18 22:26 ` Christoph Hellwig
2020-02-19 12:56 ` Christian Brauner
2020-02-18 14:34 ` [PATCH v3 16/25] attr: notify_change(): " Christian Brauner
2020-02-18 14:34 ` [PATCH v3 17/25] commoncap: cap_bprm_set_creds(): " Christian Brauner
2020-02-18 14:34 ` [PATCH v3 18/25] commoncap: cap_task_fix_setuid(): " Christian Brauner
2020-02-18 14:34 ` [PATCH v3 19/25] commoncap: handle fsid mappings with vfs caps Christian Brauner
2020-02-19 15:53 ` Jann Horn
2020-02-18 14:34 ` [PATCH v3 20/25] exec: bprm_fill_uid(): handle fsid mappings Christian Brauner
2020-02-18 14:34 ` [PATCH v3 21/25] ptrace: adapt ptrace_may_access() to always uses unmapped fsids Christian Brauner
2020-02-18 14:34 ` [PATCH v3 22/25] devpts: handle fsid mappings Christian Brauner
2020-02-18 14:34 ` [PATCH v3 23/25] keys: " Christian Brauner
2020-02-18 14:34 ` [PATCH v3 24/25] sys: handle fsid mappings in set*id() calls Christian Brauner
2020-02-19 15:42 ` Jann Horn
2020-02-18 14:34 ` [PATCH v3 25/25] selftests: add simple fsid mapping selftests Christian Brauner
2020-02-18 23:50 ` [PATCH v3 00/25] user_namespace: introduce fsid mappings James Bottomley
2020-02-19 12:27 ` Christian Brauner
2020-02-19 15:36 ` James Bottomley
2020-02-19 15:33 ` Jann Horn
2020-02-19 19:35 ` Serge E. Hallyn
2020-02-19 21:48 ` Serge E. Hallyn
2020-02-19 21:56 ` Tycho Andersen
2020-02-27 19:33 ` Josef Bacik
2020-03-02 14:34 ` Serge E. Hallyn
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