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Date: Mon, 7 Nov 2011 15:27:50 -0800
From: Greg KH <greg@kroah.com>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [kernel-hardening] Re: [PATCH] proc: restrict access to
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On Mon, Nov 07, 2011 at 11:21:32PM +0000, Alan Cox wrote:
> > It's better than nothing, but it really isn't wonderful - because it's
> > really not just about audio. And revoke doesn't work universally.
> 
> BSD invented revoke but never implemented it universally. It turns out
> that this isn't a big problem. Right now we basically only have revoke
> for tty devices but we don't need it for that much more. Revoke on disk
> files and the like has simply never happened because its not a matter of
> revoke being universal so much as universal revoke being universally
> pointless.

I looked into implementing revoke() a while ago, and looked at how BSD
did it.  They really only implemented it for a very narrow range of
devices (tty only I think), which is not what we really want.

I thought people wanted it for all char and block devices, if this isn't
so, then it might be easier to implement than I thought.

So, what do we really need revoke() for these days?

But that's getting away from the original topic here, sorry...

greg k-h