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Subject: Re: [RCF] [PATCH] unprivileged mount/umount
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Ram <linuxram@us.ibm.com>
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Date: Fri, 13 May 2005 19:44:23 +0100
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> Right but this fix disallows fchdir into a directory belonging to
> a different namespace.  And hence would disallow the ability to
> cross mount across namespaces.

A helper can still pass file handles for you, you've changed the
semantics a little (and I'm not clear if there is a need to) but I don't
see it serves any fundamental purpose. Historical experience is that
chroot exiting via fchdir is actually useful