From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Hemminger <shemminger@vyatta.com>
Subject: Re: [PATCH] sock filter: fix copy of filter from userspace
Date: Mon, 15 Oct 2012 08:57:12 -0700
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	<20121013191949.GA16286@minipsycho.orion>
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Cc: Jiri Pirko <jpirko@redhat.com>,
	"David S. Miller" <davem@davemloft.net>, netdev@vger.kernel.org
To: Jiri Pirko <jiri@resnulli.us>
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On Sat, 13 Oct 2012 21:19:49 +0200
Jiri Pirko <jiri@resnulli.us> wrote:

> Sat, Oct 13, 2012 at 08:40:32PM CEST, shemminger@vyatta.com wrote:
> >The sk_unattached_filter_create function is passed a socket
> >filter structure and the copies the contents of the filter from
> >userspace. Sparse detected that this code was incorrectly using
> >memcpy when it needed to use copy_from_user instead.
> 
> Hmm. fprog->filter is in this case allocated and filled in kernel.
> So memcpy is good.
> 
> Not sure how to handle this correctly. Either we remove "__user" or we
> redefine "struct sock_fprog" for sk_unattached_filter_create() use.
> 
> Any thoughts?

Or define a different structure for kernel usage versus userspace API.