From mboxrd@z Thu Jan  1 00:00:00 1970
From: "J. Bruce Fields" <bfields@fieldses.org>
Subject: Re: [PATCH review 6/6] vfs: Cache the results of path_connected
Date: Tue, 1 Sep 2015 14:11:22 -0400
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Cc: Andrey Vagin <avagin@openvz.org>,
	Miklos Szeredi <miklos@szeredi.hu>,
	Richard Weinberger <richard@nod.at>,
	Linux Containers <containers@lists.linux-foundation.org>,
	Andy Lutomirski <luto@amacapital.net>,
	Al Viro <viro@ZenIV.linux.org.uk>,
	linux-fsdevel@vger.kernel.org, Jann Horn <jann@thejh.net>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Willy Tarreau <w@1wt.eu>
To: "Eric W. Biederman" <ebiederm@xmission.com>
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On Tue, Sep 01, 2015 at 01:00:20PM -0500, Eric W. Biederman wrote:
> No problem.  Thank you for the discussion.  This has if nothing else
> allowed me to understand this from a real world perspective, and in
> particular allows me to understand which permission checks would be
> necessary to safely allow file handles in a user namespace (if we ever
> decide it is safe to allow that).
> 
> In short if you did not mount the filesystem you better not be nfs
> exporting the filesystem, or parts of the filesystem, or be allowed to
> use file handle access to the filesystem.

Agreed.

--b.