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Date: Fri, 21 Apr 2006 11:31:56 -0700
From: Andrew Morton <akpm@osdl.org>
To: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: grievre@gmail.com, linux-kernel@vger.kernel.org
Subject: Re: NFS bug?
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Trond Myklebust <trond.myklebust@fys.uio.no> wrote:
>
> > I'd be guessing that filldir64() was passed a negative namlen.
> 
>  Why would that trigger a bug in __copy_from_user_ll()? I could see it
>  triggering errors in copy_to_user(), but not copy_from_*...

Ah.  No, I cannot see why getdents wold run copy_from_user().

I wonder why that stack trace didn't come out.  Perhaps running `dmesg -n
7' prior to triggerng the crash will help.  (It shouldn't, but we might
have broken it).