From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] fs: generic_file_llseek_size() should recognize invalid
 whence values
Date: Fri, 28 Jun 2013 04:09:59 +0100
Message-ID: <20130628030959.GD4165@ZenIV.linux.org.uk>
References: <1372386158-11076-1-git-send-email-ryao@gentoo.org>
 <1372386158-11076-3-git-send-email-ryao@gentoo.org>
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Cc: linux-fsdevel@vger.kernel.org, kernel@gentoo.org,
	zfs-devel@zfsonlinux.org
To: Richard Yao <ryao@gentoo.org>
Return-path: <linux-fsdevel-owner@vger.kernel.org>
Received: from zeniv.linux.org.uk ([195.92.253.2]:54493 "EHLO
	ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1753743Ab3F1DKA (ORCPT
	<rfc822;linux-fsdevel@vger.kernel.org>);
	Thu, 27 Jun 2013 23:10:00 -0400
Content-Disposition: inline
In-Reply-To: <1372386158-11076-3-git-send-email-ryao@gentoo.org>
Sender: linux-fsdevel-owner@vger.kernel.org
List-ID: <linux-fsdevel.vger.kernel.org>

On Thu, Jun 27, 2013 at 10:22:38PM -0400, Richard Yao wrote:
> generic_file_llseek_size() handles whence values in a switch statement,
> but it lacks cases for both SEEK_SET and invalid values. This causes it
> to treat all invalid whence values as SEEK_SET, which is wrong.
> 
> We fix that by adding a case for SEEK_SET and a default case.

NAK.  Validation of whence is done before we even get to vfs_llseek().
Leaving it to ->llseek() instances would've been an insanity.