From: Matt McCutchen <matt@mattmccutchen.net>
Subject: Re: [PATCH #3] reiserfs: Fix permissions on .reiserfs_priv
Date: Thu, 08 Apr 2010 18:39:27 -0400
Message-ID: <1270766367.3441.4.camel@mattlaptop2.local>
References: <4BBE42A9.2010506@suse.com>  <4BBE4CE2.8030805@gmail.com>
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To: ReiserFS Mailing List <reiserfs-devel@vger.kernel.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Cc: Edward Shishkin <edward.shishkin@gmail.com>, Andrew Morton <akpm@linux-foundation.org>, Jeff Mahoney <jeffm@suse.com>

On Thu, 2010-04-08 at 23:38 +0200, Edward Shishkin wrote:
> Jeff Mahoney wrote:
> >  [...] This patch resolves the issue by properly hiding .reiserfs_priv. This
> >  was the intent of the xattr poisoning code, but it appears to have
> >  never worked as expected. This is fixed by using d_revalidate instead
> >  of d_compare. [...]

The patch seems to rely on the fact that the priv_root dentry is stuck
in the dcache for as long as the filesystem is mounted, so that attempts
to follow ".reiserfs_priv" are guaranteed to match that dentry in the
cache and be refused by xattr_hide_revalidate.  Is my understanding
correct?

-- 
Matt