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Date: Fri, 14 Jan 2011 19:09:23 -0500 (EST)
From: Rick Macklem <rmacklem@uoguelph.ca>
To: Daniel Braniss <danny@cs.huji.ac.il>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: NFS: file too large
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> 
> BTW, why not make away with the test altogether?
> 
Well, since a server specifies the maximum file size it can
handle, it seems good form to check for that in the client.
(Although I'd agree that a server shouldn't crash if a read/write
 that goes beyond that limit.)

Also, as Matt notes, off_t is signed. As such, it looks to me like
the check could mess up if uio_offset it right near 0x7fffffffffffffff,
so that uio->ui_offset + uio->uio_resid ends up negative. I think the
check a little above that for uio_offset < 0 should also check
uio_offset + uio_resid < 0 to avoid this.

rick