From owner-freebsd-current@FreeBSD.ORG  Fri Jan 28 12:59:23 2005
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To: "Mark W. Krentel" <krentel@dreamscape.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 27 Jan 2005 21:54:22 EST."
             <200501280254.j0S2sMJH050277@blue.mwk.domain> 
Date: Fri, 28 Jan 2005 13:59:15 +0100
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cc: freebsd-current@freebsd.org
cc: alc@cs.rice.edu
cc: Kris Kennaway <kris@obsecurity.org>
Subject: Re: fstat triggered INVARIANTS panic in memrw() 
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In message <200501280254.j0S2sMJH050277@blue.mwk.domain>, "Mark W. Krentel" writes:
>I've looked a little deeper into Kris's fstat panic.
>Turns out there are bugs in three places.
>
>(1) fstat(1) sometimes calls kvm_read() with a ridiculously out-of-
>bounds value for nbytes.

The only real problem here is that fstat(1) uses kvm in the first place.
The necessary information should be exported via sysctls.

No program used as part of regular system operation should use kvm.

-- 
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.