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Date: Mon, 8 Mar 2010 10:59:11 -0800 (PST)
From: Linus Torvalds <torvalds@linux-foundation.org>
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To: Al Viro <viro@ZenIV.linux.org.uk>
cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, Ingo Molnar <mingo@elte.hu>,
       James Morris <jmorris@namei.org>, linux-kernel@vger.kernel.org,
       Kyle McMartin <kyle@mcmartin.ca>,
       Alexander Viro <viro@ftp.linux.org.uk>
Subject: Re: Upstream first policy
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On Mon, 8 Mar 2010, Al Viro wrote:
> > 
> > I really don't understand why some people are unable to admit this fact. 
> 
> Because you don't have to use that pathname to modify the bits returned
> by read() after open() on that pathname?

The thing is, I don't think it's an "either or".

Sure, there is content security. Nobody disputes that. The security 
decision about how to open a file is about the contents of the file.

So I'm not suggesting we _replace_ content-based security with 
pathname-based security. I'm just saying that pathnames actually do matter 
for security, and that they are an independent issue.

> I'm not fond of selinux, to put it mildly, but "pathname-based" stuff simply
> doesn't match how the pathname resolution is defined on Unix...

Again, I'm not claiming that we should change how "open" works and has 
always worked. I don't even understand why you have that crazy "either or" 
mentality to begin with. Why?

It's not "either pathname or inode". I'm saying _both_ make sense. 

In some situations, the name itself really is what is fundamentally 
special about the file.

		Linus