From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932098AbcEaLwN (ORCPT ); Tue, 31 May 2016 07:52:13 -0400 Received: from mail-am1on0148.outbound.protection.outlook.com ([157.56.112.148]:41697 "EHLO emea01-am1-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751484AbcEaLwJ (ORCPT ); Tue, 31 May 2016 07:52:09 -0400 Authentication-Results: vger.kernel.org; dkim=none (message not signed) header.d=none;vger.kernel.org; dmarc=none action=none header.from=virtuozzo.com; Subject: Re: [PATCH] mm, kasan: introduce a special shadow value for allocator metadata To: Alexander Potapenko , , , , , , , , References: <1464691466-59010-1-git-send-email-glider@google.com> CC: , , From: Andrey Ryabinin Message-ID: <574D7B11.8090709@virtuozzo.com> Date: Tue, 31 May 2016 14:52:49 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.8.0 MIME-Version: 1.0 In-Reply-To: <1464691466-59010-1-git-send-email-glider@google.com> Content-Type: text/plain; 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However a write to the kmalloc metadata may cause > memory corruptions that will make the tool itself unreliable and induce > crashes later on. Warning about such corruptions will ease the > debugging. It will not. Whether out-of-bounds hits metadata or not is absolutely irrelevant to the bug itself. This information doesn't help to understand, analyze or fix the bug.