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Date: Fri, 20 Mar 2015 13:31:18 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Karel Zak <kzak@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>, linux-kernel@vger.kernel.org
Subject: Re: d_path() and overlay fs
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On Fri, Mar 20, 2015 at 02:29:14PM +0100, Karel Zak wrote:

>  It seems like serious problem because kernel uses d_path() (and
>  friends) on many places to generate path strings for userspace in
>  /proc and /sys and people already use overlay fs in containers.

It's not d_path(), it's file->f_path being wrong to start with.  Same
problem as what dhowells is fighting wrt LSM shite.