From owner-freebsd-current@FreeBSD.ORG  Tue Nov 18 23:20:41 2003
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To: Ian Dowse <iedowse@maths.tcd.ie>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 18 Nov 2003 22:53:42 GMT."
             <200311182253.aa25788@salmon.maths.tcd.ie> 
Date: Wed, 19 Nov 2003 08:20:34 +0100
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cc: Rudolf Cejka <cejkar@fit.vutbr.cz>
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cc: "Tim J. Robbins" <tjr@freebsd.org>
Subject: Re: cvs commit: src/sbin/umount umount.c 
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In message <200311182253.aa25788@salmon.maths.tcd.ie>, Ian Dowse writes:

>I was planning to return a filesystem ID of {st_dev, 0} to non-root
>users,

Please notice that st_dev is not constant across reboots.

Suggest you hash the real fsid and use the hash instead.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.