Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 17 Oct 2002 12:45:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 17 Oct 2002 12:45:48 -0400 Received: from mithra.wirex.com ([65.102.14.2]:58890 "EHLO mail.wirex.com") by vger.kernel.org with ESMTP id ; Thu, 17 Oct 2002 12:45:46 -0400 Message-ID: <3DAEEA7A.6000803@wirex.com> Date: Thu, 17 Oct 2002 09:51:06 -0700 From: Crispin Cowan Organization: WireX Communications, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.1) Gecko/20020827 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Greg KH Cc: Christoph Hellwig , torvalds@transmeta.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] make LSM register functions GPLonly exports References: <20021017153505.A27998@infradead.org> <20021017150740.GA31056@kroah.com> X-Enigmail-Version: 0.65.2.0 X-Enigmail-Supports: pgp-inline, pgp-mime Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="------------enigF14B24A9121C81991429F048" Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3411 Lines: 84 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigF14B24A9121C81991429F048 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Greg KH wrote: >On Thu, Oct 17, 2002 at 03:35:05PM +0100, Christoph Hellwig wrote: > > >>These exports have the power to change the implementations of all >>syscalls and I've seen people exploiting this "feature". >> >>Make the exports GPLonly (which some LSM folks agreed to >>when it was merged initially to avoid that). >> >> >I would really, really, really like to make this change. Unfortunatly, >one of the current copyright holders of this file does not agree with >it. > >Crispin, for the benifit of the lkml readers, can you explain why WireX >does not want this change? > Here's the monster flame-war we had the last time this issue was debated http://www.uwsg.iu.edu/hypermail/linux/kernel/0109.3/0102.html My argument against the intent of this change is that no, I do not think we should restrict LSM modules to be GPL-only. LSM is an API for loading externally developed packages of software, similar to syscalls. There is benefit in permitting proprietary modules (you get additional modules that you would not get otherwise) just as there is benefit in permitting proprietary applications (you get Oracle, DB2, and WordPerfect). My argument against the implementation technique of dropping in these export GPLonly symbols is that my read of the GPL itself means that they have no legal impact. The crux of the matter is whether a *court* finds that LSM is "linking" (in the GPL sense) or is an "interface": * If it is "linking": then all LSM modules end up GPL'd, regardless of what any of us want. * If it is "an interface": then the GPL specifically *prohibits* you from imposing additional restrictions, such as requiring someone else's module to be GPL'd, to wit: o Clause 4: "You may not copy, modify, sublicense, or distribute the Program except as expressly provided under this License." o Clause 6: "... You may not impose any further restrictions on the recipients' exercise of the rights granted herein." Therefore, the EXPORT_SYMBOL_GPL is just a bunch of useless bloat, with no legal standing what so ever. If kernel module interfaces are held by a court to be linking, then export symbols are redundant. If kernel module interfaces are held by a court to be an interface, then the export symbols are just wrong. Crispin -- Crispin Cowan, Ph.D. Chief Scientist, WireX http://wirex.com/~crispin/ Security Hardened Linux Distribution: http://immunix.org Available for purchase: http://wirex.com/Products/Immunix/purchase.html --------------enigF14B24A9121C81991429F048 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.6 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQE9ruqC5ZkfjX2CNDARAb9oAJ0Rfcs1AmzFcThwMu6LwjYk53kNFgCg3Pr7 ZRqO8UZlVjmiWuDqa1W7XUM= =5oBb -----END PGP SIGNATURE----- --------------enigF14B24A9121C81991429F048-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/