From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751770Ab1F0SMe (ORCPT ); Mon, 27 Jun 2011 14:12:34 -0400 Received: from mail.candelatech.com ([208.74.158.172]:46742 "EHLO ns3.lanforge.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753068Ab1F0SM3 (ORCPT ); Mon, 27 Jun 2011 14:12:29 -0400 Message-ID: <4E08C80B.9070602@candelatech.com> Date: Mon, 27 Jun 2011 11:12:27 -0700 From: Ben Greear Organization: Candela Technologies User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100430 Fedora/3.0.4-2.fc11 Thunderbird/3.0.4 MIME-Version: 1.0 To: Linux Kernel Mailing List Subject: Question on debugging use-after-free memory issues. Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org I have a case where deleted memory is being passed into an RPC callback. I enabled SLUB memory poisoning and verified that the data pointed to has 0x6b...6b value. Unfortunately, the rpc code is a giant maze of callbacks and I'm having a difficult time figuring out where this data could be erroneously deleted at. So first question: Given a pointer to memory, and with SLUB memory debuging on (and/or other debugging options if applicable), is there a way to get any info about where the memory was last deleted? Second: Any other suggestions for how to go about debugging this? I hit this problem under load after multiple hours, so just adding printks in random places may not be feasible... Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com