From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: Linux 2.6.26-rc4
Date: Tue, 3 Jun 2008 11:52:58 +0100
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To: Miklos Szeredi <miklos@szeredi.hu>
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On Tue, Jun 03, 2008 at 12:45:33PM +0200, Miklos Szeredi wrote:

> I think it must be autofs4 doing something weird.  Like this in
> autofs4_lookup_unhashed():
> 
> 			/*
> 			 * Make the rehashed dentry negative so the VFS
> 			 * behaves as it should.
> 			 */
> 			if (inode) {
> 				dentry->d_inode = NULL;

Lovely.  If we ever step into that with somebody else (no matter who)
holding a reference to that dentry, we are certainly well and truly
buggered.  It's not just mount(2) - everything in the tree assumes that
holding a reference to positive dentry guarantees that it remains
positive.

Ian?