From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932722AbaKRVKx (ORCPT ); Tue, 18 Nov 2014 16:10:53 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:28063 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754787AbaKRVKw (ORCPT ); Tue, 18 Nov 2014 16:10:52 -0500 Message-ID: <546BB58A.4080209@oracle.com> Date: Tue, 18 Nov 2014 16:09:30 -0500 From: Sasha Levin User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: Andrew Morton , Andrey Ryabinin CC: Dmitry Vyukov , Konstantin Serebryany , Dmitry Chernenkov , Andrey Konovalov , Yuri Gribov , Konstantin Khlebnikov , Michal Marek , Thomas Gleixner , Ingo Molnar , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Dave Hansen , Andi Kleen , Vegard Nossum , "H. Peter Anvin" , x86@kernel.org, linux-mm@kvack.org, Randy Dunlap , Peter Zijlstra , Alexander Viro , Dave Jones , Jonathan Corbet , Joe Perches , linux-kernel@vger.kernel.org Subject: Re: [PATCH v6 00/11] Kernel address sanitizer - runtime memory debugger. References: <1404905415-9046-1-git-send-email-a.ryabinin@samsung.com> <1415199241-5121-1-git-send-email-a.ryabinin@samsung.com> <5461B906.1040803@samsung.com> <20141118125843.434c216540def495d50f3a45@linux-foundation.org> In-Reply-To: <20141118125843.434c216540def495d50f3a45@linux-foundation.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit X-Source-IP: ucsinet21.oracle.com [156.151.31.93] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/18/2014 03:58 PM, Andrew Morton wrote: > On Tue, 11 Nov 2014 10:21:42 +0300 Andrey Ryabinin wrote: > >> Hi Andrew, >> >> Now we have stable GCC(4.9.2) which supports kasan and from my point of view patchset is ready for merging. >> I could have sent v7 (it's just rebased v6), but I see no point in doing that and bothering people, >> unless you are ready to take it. > > It's a huge pile of tricky code we'll need to maintain. To justify its > inclusion I think we need to be confident that kasan will find a > significant number of significant bugs that > kmemcheck/debug_pagealloc/slub_debug failed to detect. > > How do we get that confidence? I've seen a small number of > minorish-looking kasan-detected bug reports go past, maybe six or so. > That's in a 20-year-old code base, so one new minor bug discovered per > three years? Not worth it! It's worth noting here that not all bugs discovered by kasan belong to the -mm tree. Bugs which are more severe, such as: http://openwall.com/lists/oss-security/2014/07/17/1 Are the result of fuzzing with kasan. So while it's indeed not a huge number, it's way more than 6 and not only minor issues. Thanks, Sasha From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f49.google.com (mail-oi0-f49.google.com [209.85.218.49]) by kanga.kvack.org (Postfix) with ESMTP id 034E96B006C for ; Tue, 18 Nov 2014 16:10:26 -0500 (EST) Received: by mail-oi0-f49.google.com with SMTP id i138so2033607oig.22 for ; Tue, 18 Nov 2014 13:10:25 -0800 (PST) Received: from userp1040.oracle.com (userp1040.oracle.com. [156.151.31.81]) by mx.google.com with ESMTPS id o5si25729017oig.56.2014.11.18.13.10.24 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Tue, 18 Nov 2014 13:10:25 -0800 (PST) Message-ID: <546BB58A.4080209@oracle.com> Date: Tue, 18 Nov 2014 16:09:30 -0500 From: Sasha Levin MIME-Version: 1.0 Subject: Re: [PATCH v6 00/11] Kernel address sanitizer - runtime memory debugger. References: <1404905415-9046-1-git-send-email-a.ryabinin@samsung.com> <1415199241-5121-1-git-send-email-a.ryabinin@samsung.com> <5461B906.1040803@samsung.com> <20141118125843.434c216540def495d50f3a45@linux-foundation.org> In-Reply-To: <20141118125843.434c216540def495d50f3a45@linux-foundation.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Andrey Ryabinin Cc: Dmitry Vyukov , Konstantin Serebryany , Dmitry Chernenkov , Andrey Konovalov , Yuri Gribov , Konstantin Khlebnikov , Michal Marek , Thomas Gleixner , Ingo Molnar , Christoph Lameter , Pekka Enberg , David Rientjes , Joonsoo Kim , Dave Hansen , Andi Kleen , Vegard Nossum , "H. Peter Anvin" , x86@kernel.org, linux-mm@kvack.org, Randy Dunlap , Peter Zijlstra , Alexander Viro , Dave Jones , Jonathan Corbet , Joe Perches , linux-kernel@vger.kernel.org On 11/18/2014 03:58 PM, Andrew Morton wrote: > On Tue, 11 Nov 2014 10:21:42 +0300 Andrey Ryabinin wrote: > >> Hi Andrew, >> >> Now we have stable GCC(4.9.2) which supports kasan and from my point of view patchset is ready for merging. >> I could have sent v7 (it's just rebased v6), but I see no point in doing that and bothering people, >> unless you are ready to take it. > > It's a huge pile of tricky code we'll need to maintain. To justify its > inclusion I think we need to be confident that kasan will find a > significant number of significant bugs that > kmemcheck/debug_pagealloc/slub_debug failed to detect. > > How do we get that confidence? I've seen a small number of > minorish-looking kasan-detected bug reports go past, maybe six or so. > That's in a 20-year-old code base, so one new minor bug discovered per > three years? Not worth it! It's worth noting here that not all bugs discovered by kasan belong to the -mm tree. Bugs which are more severe, such as: http://openwall.com/lists/oss-security/2014/07/17/1 Are the result of fuzzing with kasan. So while it's indeed not a huge number, it's way more than 6 and not only minor issues. Thanks, Sasha -- 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