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=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 BE0C0C4332E for ; Fri, 5 Feb 2021 02:41:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A6B5C64E7B for ; Fri, 5 Feb 2021 02:41:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229693AbhBEClE (ORCPT ); Thu, 4 Feb 2021 21:41:04 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:39148 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229741AbhBECkx (ORCPT ); Thu, 4 Feb 2021 21:40:53 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612492765; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=W5bn83n8Mnv4jhBjQZjCE0HJfiM3n4fNsp/V9eJl1PE=; b=cOLu8m4KPROK8AUdK9B3Gdwqm8/+aUZltWVTmfUubOHitKE4lmB9VknOpPb24zHGupU8Po jIh8iqRO+mKNsJ6sT4bJydI4ff1gwlbVzMuV7kCyLGx7gv6HXDiJdAdHJvOJnuFaMow0kb eIyfFwvcLgFt6OjHcB44oJRMFgjVIlI= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-150-rxueXqjkMfWAm_nysfAjig-1; Thu, 04 Feb 2021 21:39:21 -0500 X-MC-Unique: rxueXqjkMfWAm_nysfAjig-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D4E3CBBEE5; Fri, 5 Feb 2021 02:39:19 +0000 (UTC) Received: from T590 (ovpn-13-14.pek2.redhat.com [10.72.13.14]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 819451002391; Fri, 5 Feb 2021 02:39:10 +0000 (UTC) Date: Fri, 5 Feb 2021 10:39:06 +0800 From: Ming Lei To: John Garry Cc: Bart Van Assche , pragalla@codeaurora.org, axboe@kernel.dk, evgreen@google.com, jianchao.w.wang@oracle.com, linux-block@vger.kernel.org, stummala@codeaurora.org Subject: Re: use-after-free access in bt_iter() Message-ID: <20210205023906.GB1498829@T590> References: <056783fa-a510-2463-f353-c64dd8f37be9@acm.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Thu, Feb 04, 2021 at 04:17:51PM +0000, John Garry wrote: > 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. > If still no progress, I'd suggest to consider the patches I posted: https://lore.kernel.org/linux-block/accb98d8-8186-2e74-a5c3-e0f09ce2b3ff@acm.org/#r The idea is quite simple at least, :-) -- Ming