From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pl0-f71.google.com (mail-pl0-f71.google.com [209.85.160.71]) by kanga.kvack.org (Postfix) with ESMTP id 3327C6B0006 for ; Wed, 7 Mar 2018 12:27:01 -0500 (EST) Received: by mail-pl0-f71.google.com with SMTP id n12-v6so1418076pls.12 for ; Wed, 07 Mar 2018 09:27:01 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id t4-v6sor5750393plb.45.2018.03.07.09.26.59 for (Google Transport Security); Wed, 07 Mar 2018 09:26:59 -0800 (PST) Subject: Re: [PATCH 6/7] lkdtm: crash on overwriting protected pmalloc var References: <20180228200620.30026-1-igor.stoppa@huawei.com> <20180228200620.30026-7-igor.stoppa@huawei.com> <1723ee8d-c89e-0704-c2c3-254eda39dc8b@gmail.com> <6378e63e-174f-642e-d319-1d121b74d3d7@huawei.com> From: J Freyensee Message-ID: <2664691b-4d48-1701-8dae-774ec7733f61@gmail.com> Date: Wed, 7 Mar 2018 09:26:55 -0800 MIME-Version: 1.0 In-Reply-To: <6378e63e-174f-642e-d319-1d121b74d3d7@huawei.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: owner-linux-mm@kvack.org List-ID: To: Igor Stoppa , david@fromorbit.com, willy@infradead.org, keescook@chromium.org, mhocko@kernel.org Cc: labbott@redhat.com, linux-security-module@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, kernel-hardening@lists.openwall.com On 3/7/18 5:18 AM, Igor Stoppa wrote: > > On 06/03/18 19:20, J Freyensee wrote: > >> On 2/28/18 12:06 PM, Igor Stoppa wrote: > [...] > >>> void __init lkdtm_perms_init(void); >>> void lkdtm_WRITE_RO(void); >>> void lkdtm_WRITE_RO_AFTER_INIT(void); >>> +void lkdtm_WRITE_RO_PMALLOC(void); >> Does this need some sort of #ifdef too? > Not strictly. It's just a function declaration. > As long as it is not used, the linker will not complain. > The #ifdef placed around the use and definition is sufficient, from a > correctness perspective. > > But it's a different question if there is any standard in linux about > hiding also the declaration. I'd prefer hiding it if it's contents are being ifdef'ed out, but I really think it's more of a maintainer preference question. > > I am not very fond of #ifdefs, so when I can I try to avoid them. > > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org