From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.4 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 20ABAC433E0 for ; Thu, 4 Feb 2021 16:20:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CB96664E4F for ; Thu, 4 Feb 2021 16:20:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237279AbhBDQUu (ORCPT ); Thu, 4 Feb 2021 11:20:50 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]:2495 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237723AbhBDQUL (ORCPT ); Thu, 4 Feb 2021 11:20:11 -0500 Received: from fraeml743-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4DWkDk2flJz67kpt; Fri, 5 Feb 2021 00:15:50 +0800 (CST) Received: from lhreml724-chm.china.huawei.com (10.201.108.75) by fraeml743-chm.china.huawei.com (10.206.15.224) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Thu, 4 Feb 2021 17:19:22 +0100 Received: from [10.210.168.183] (10.210.168.183) by lhreml724-chm.china.huawei.com (10.201.108.75) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2106.2; Thu, 4 Feb 2021 16:19:20 +0000 Subject: Re: use-after-free access in bt_iter() To: Bart Van Assche , , , , CC: , , Ming Lei References: <056783fa-a510-2463-f353-c64dd8f37be9@acm.org> From: John Garry Message-ID: Date: Thu, 4 Feb 2021 16:17:51 +0000 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.1.2 MIME-Version: 1.0 In-Reply-To: <056783fa-a510-2463-f353-c64dd8f37be9@acm.org> Content-Type: text/plain; charset="utf-8"; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.210.168.183] X-ClientProxiedBy: lhreml719-chm.china.huawei.com (10.201.108.70) To lhreml724-chm.china.huawei.com (10.201.108.75) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On 04/02/2021 15:51, Bart Van Assche wrote: > On 2/4/21 3:46 AM,pragalla@codeaurora.org wrote: >> Is this issue got fixed on any latest kernel ? if so, can you please >> help point the patch ? >> If not got fixed, can we have a final solution ? i can even help in >> testing the solution. > Hi John, > Hi Bart, > Some time ago you replied the following to an email from me with a > suggestion for a fix: "Please let me consider it a bit more." Are you > still working on a fix? Unfortunately I have not had a chance, sorry. But I can look again. So I have only seen KASAN use-after-free's myself, but never an actual oops. IIRC, someone did report an oops. @Pradeep, do you have a reliable re-creator? I noticed the timeout handler stackframe in your mail, so I guess not. However, as an experiment, could you test: https://lore.kernel.org/linux-block/1608203273-170555-2-git-send-email-john.garry@huawei.com/ This should fix the common issue. But no final solution to issues discussed from patch 2/2, which is more exotic. BTW, is this the same Pradeep who reported: https://lore.kernel.org/linux-block/1606402925-24420-1-git-send-email-ppvk@codeaurora.org/ I did cc ppvk@codeaurora.org on earlier version of my series, but it bounced. > > See also > https://lore.kernel.org/linux-block/1bcc1d9e-6a32-1e00-0d32-f5b7325b2f8c@huawei.com/ Thanks, John