From: Andy Whitcroft <apw@canonical.com>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: "Serge Hallyn" <serge.hallyn@ubuntu.com>,
Linux-Fsdevel <linux-fsdevel@vger.kernel.org>,
kernel-team@lists.ubuntu.com,
"Stéphane Graber" <stephane.graber@canonical.com>
Subject: Re: [PATCH RFC] overlayfs,xattr: allow unprivileged users to whiteout
Date: Fri, 28 Feb 2014 14:55:14 +0000 [thread overview]
Message-ID: <20140228145514.GD4334@dm> (raw)
In-Reply-To: <CAJfpegvNZAORrBO7tiZ-McoVLO94o17WUCo8sGzDso3N_wn-TA@mail.gmail.com>
On Fri, Feb 28, 2014 at 03:15:14PM +0100, Miklos Szeredi wrote:
> On Tue, Feb 25, 2014 at 6:31 PM, Serge Hallyn <serge.hallyn@ubuntu.com> wrote:
> > To mark a file which exists in the lower layer as deleted,
> > it creates a symbolic link to a file called "(overlay-whiteout)"
> > in the writeable mount, and sets a "trusted.overlay" xattr
> > on that link.
> >
> > 1. When the create the symbolic link as container root, not
> > as the global root
> >
> > 2. Allow root in a container to edit "trusted.overlay*"
> > xattrs. Generally only global root is allowed to edit
> > "trusted.*"
>
> Shouldn't overlayfs just skip the permission checks and call
> __vfs_setxattr_noperm() instead?
It does seem we should be avoiding the permissions here, as we have let
the thing be mounted we have done the permissions checks for that and for
the file access itself already. This operation is something we definatly
want to represent in the filesystem.
-apw
next prev parent reply other threads:[~2014-02-28 14:55 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-02-25 17:31 [PATCH RFC] overlayfs,xattr: allow unprivileged users to whiteout Serge Hallyn
2014-02-28 14:15 ` Miklos Szeredi
2014-02-28 14:55 ` Andy Whitcroft [this message]
2014-02-28 16:23 ` Serge Hallyn
2014-03-05 17:46 ` [RFC] overlayfs priviledge escalation handling under user namespaces Andy Whitcroft
2014-03-05 17:46 ` [RFC PATCH 1/1] overlayfs: switch to the init user namespace for xattr operations Andy Whitcroft
2014-03-05 17:46 ` [RFC PATCH 1/1] overlayfs: use kernel service credentials for copy up and xattr manipulations Andy Whitcroft
2014-03-05 20:01 ` Serge Hallyn
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=20140228145514.GD4334@dm \
--to=apw@canonical.com \
--cc=kernel-team@lists.ubuntu.com \
--cc=linux-fsdevel@vger.kernel.org \
--cc=miklos@szeredi.hu \
--cc=serge.hallyn@ubuntu.com \
--cc=stephane.graber@canonical.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;
as well as URLs for NNTP newsgroup(s).