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Date: Thu, 27 Sep 2007 07:23:16 -0400
From: Theodore Tso <tytso@mit.edu>
To: Christer Weinigel <christer@weinigel.se>
Cc: David Newall <david@davidnewall.com>, Al Viro <viro@ftp.linux.org.uk>,
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       majkls <majkls@prepere.com>, bunk@fs.tum.de,
       linux-kernel@vger.kernel.org
Subject: Re: sys_chroot+sys_fchdir Fix
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On Thu, Sep 27, 2007 at 09:28:08AM +0200, Christer Weinigel wrote:
> So the OpenBSD man page seems to be in the minority here.  Any portable
> code can not assume that CWD changes.  And changing the Linux behaviour
> now would be a rather big change which might break userspace.  And yes,
> there are applications that rely on this, I've used it when building
> software for cross compiling.  

Changing Linux behavior would violate the POSIX and SuSV2
specifications; the standards explicitly state that the working
directory will NOT change.  And standards adherance is important; we
break them only if we have a d*mn good reason.  And trying to make
chroot() something which it is not (i.e., a secure jail) is certainly
not a good enough reason.

Can we please end this thread now?  And can we put in a Kernel FAQ
saying that this is not something which is NOT up for discussion?

       	    	    		  	   - Ted
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