From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 23C8EC433DF for ; Tue, 11 Aug 2020 08:09:36 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id 7D8EB2065C for ; Tue, 11 Aug 2020 08:09:35 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7D8EB2065C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=ACULAB.COM Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19586-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 9352 invoked by uid 550); 11 Aug 2020 08:09:27 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 9332 invoked from network); 11 Aug 2020 08:09:27 -0000 X-MC-Unique: 6yjApz6GO-e2kdqAupHRLw-1 From: David Laight To: =?iso-8859-1?Q?=27Micka=EBl_Sala=FCn=27?= , Al Viro CC: Kees Cook , Andrew Morton , "linux-kernel@vger.kernel.org" , Aleksa Sarai , "Alexei Starovoitov" , Andy Lutomirski , "Christian Brauner" , Christian Heimes , Daniel Borkmann , Deven Bowers , Dmitry Vyukov , "Eric Biggers" , Eric Chiang , "Florian Weimer" , James Morris , Jan Kara , Jann Horn , Jonathan Corbet , Lakshmi Ramasubramanian , Matthew Garrett , Matthew Wilcox , Michael Kerrisk , Mimi Zohar , =?iso-8859-1?Q?Philippe_Tr=E9buchet?= , "Scott Shell" , Sean Christopherson , Shuah Khan , Steve Dower , Steve Grubb , Tetsuo Handa , Thibaut Sautereau , Vincent Strubel , "kernel-hardening@lists.openwall.com" , "linux-api@vger.kernel.org" , "linux-integrity@vger.kernel.org" , "linux-security-module@vger.kernel.org" , "linux-fsdevel@vger.kernel.org" Subject: RE: [PATCH v7 0/7] Add support for O_MAYEXEC Thread-Topic: [PATCH v7 0/7] Add support for O_MAYEXEC Thread-Index: AQHWb1PwbfAzth+cK0yvrOzhTaEjE6kx5WiAgAAMbuyAAJu5IA== Date: Tue, 11 Aug 2020 08:09:10 +0000 Message-ID: <26a4a8378f3b4ad28eaa476853092716@AcuMS.aculab.com> References: <20200723171227.446711-1-mic@digikod.net> <202007241205.751EBE7@keescook> <0733fbed-cc73-027b-13c7-c368c2d67fb3@digikod.net> <20200810202123.GC1236603@ZenIV.linux.org.uk> <30b8c003f49d4280be5215f634ca2c06@AcuMS.aculab.com> <20200810222838.GF1236603@ZenIV.linux.org.uk> <2531a0e8-5122-867c-ba06-5d2e623a3834@digikod.net> In-Reply-To: <2531a0e8-5122-867c-ba06-5d2e623a3834@digikod.net> Accept-Language: en-GB, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.202.205.107] MIME-Version: 1.0 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=C51A453 smtp.mailfrom=david.laight@aculab.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: aculab.com Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable > On 11/08/2020 00:28, Al Viro wrote: > > On Mon, Aug 10, 2020 at 10:09:09PM +0000, David Laight wrote: > >>> On Mon, Aug 10, 2020 at 10:11:53PM +0200, Micka=C3=ABl Sala=C3=BCn wr= ote: > >>>> It seems that there is no more complains nor questions. Do you want = me > >>>> to send another series to fix the order of the S-o-b in patch 7? > >>> > >>> There is a major question regarding the API design and the choice of > >>> hooking that stuff on open(). And I have not heard anything resembli= ng > >>> a coherent answer. > >> > >> To me O_MAYEXEC is just the wrong name. > >> The bit would be (something like) O_INTERPRET to indicate > >> what you want to do with the contents. >=20 > The properties is "execute permission". This can then be checked by > interpreters or other applications, then the generic O_MAYEXEC name. The english sense of MAYEXEC is just wrong for what you are trying to check. > > ... which does not answer the question - name of constant is the least = of > > the worries here. Why the hell is "apply some unspecified checks to > > file" combined with opening it, rather than being an independent primit= ive > > you apply to an already opened file? Just in case - "'cuz that's how w= e'd > > done it" does not make a good answer... Maybe an access_ok() that acts on an open fd would be more appropriate. Which might end up being an fcntrl() action. That would give you a full 32bit mask of options. =09David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1= PT, UK Registration No: 1397386 (Wales)