From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754730AbdDRGlc (ORCPT ); Tue, 18 Apr 2017 02:41:32 -0400 Received: from mx2.suse.de ([195.135.220.15]:40247 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751719AbdDRGla (ORCPT ); Tue, 18 Apr 2017 02:41:30 -0400 Date: Tue, 18 Apr 2017 08:41:25 +0200 From: Michal Hocko To: Christoph Lameter Cc: Kees Cook , Andrew Morton , Pekka Enberg , David Rientjes , Joonsoo Kim , Linux-MM , LKML Subject: Re: [PATCH] mm: Add additional consistency check Message-ID: <20170418064124.GA22360@dhcp22.suse.cz> References: <20170411141956.GP6729@dhcp22.suse.cz> <20170411164134.GA21171@dhcp22.suse.cz> <20170411183035.GD21171@dhcp22.suse.cz> <20170411185555.GE21171@dhcp22.suse.cz> <20170411193948.GA29154@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon 17-04-17 10:22:29, Cristopher Lameter wrote: > On Tue, 11 Apr 2017, Michal Hocko wrote: > > > On Tue 11-04-17 13:59:44, Cristopher Lameter wrote: > > > On Tue, 11 Apr 2017, Michal Hocko wrote: > > > > > > > I didn't say anything like that. Hence the proposed patch which still > > > > needs some more thinking and evaluation. > > > > > > This patch does not even affect kfree(). > > > > Ehm? Are we even talking about the same thing? The whole discussion was > > to catch invalid pointers to _kfree_ and why BUG* is not the best way to > > handle that. > > The patch does not do that. See my review. Invalid points to kfree are > already caught with a bug on. See kfree in mm/slub.c Are you even reading those emails? First of all we are talking about slab here. Secondly I've already pointed out that the BUG_ON(!PageSlab) in kmem_freepages is already too late because we do operate on a potential garbage from invalid page... -- Michal Hocko SUSE Labs From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f69.google.com (mail-wm0-f69.google.com [74.125.82.69]) by kanga.kvack.org (Postfix) with ESMTP id 9B90F6B0038 for ; Tue, 18 Apr 2017 02:41:31 -0400 (EDT) Received: by mail-wm0-f69.google.com with SMTP id h65so2186533wmd.7 for ; Mon, 17 Apr 2017 23:41:31 -0700 (PDT) Received: from mx1.suse.de (mx2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id r2si19282717wra.223.2017.04.17.23.41.29 for (version=TLS1 cipher=AES128-SHA bits=128/128); Mon, 17 Apr 2017 23:41:30 -0700 (PDT) Date: Tue, 18 Apr 2017 08:41:25 +0200 From: Michal Hocko Subject: Re: [PATCH] mm: Add additional consistency check Message-ID: <20170418064124.GA22360@dhcp22.suse.cz> References: <20170411141956.GP6729@dhcp22.suse.cz> <20170411164134.GA21171@dhcp22.suse.cz> <20170411183035.GD21171@dhcp22.suse.cz> <20170411185555.GE21171@dhcp22.suse.cz> <20170411193948.GA29154@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: Christoph Lameter Cc: Kees Cook , Andrew Morton , Pekka Enberg , David Rientjes , Joonsoo Kim , Linux-MM , LKML On Mon 17-04-17 10:22:29, Cristopher Lameter wrote: > On Tue, 11 Apr 2017, Michal Hocko wrote: > > > On Tue 11-04-17 13:59:44, Cristopher Lameter wrote: > > > On Tue, 11 Apr 2017, Michal Hocko wrote: > > > > > > > I didn't say anything like that. Hence the proposed patch which still > > > > needs some more thinking and evaluation. > > > > > > This patch does not even affect kfree(). > > > > Ehm? Are we even talking about the same thing? The whole discussion was > > to catch invalid pointers to _kfree_ and why BUG* is not the best way to > > handle that. > > The patch does not do that. See my review. Invalid points to kfree are > already caught with a bug on. See kfree in mm/slub.c Are you even reading those emails? First of all we are talking about slab here. Secondly I've already pointed out that the BUG_ON(!PageSlab) in kmem_freepages is already too late because we do operate on a potential garbage from invalid page... -- Michal Hocko SUSE Labs -- 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