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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, 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 BCFB0C4332D for ; Sun, 22 Mar 2020 01:55:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 812F520757 for ; Sun, 22 Mar 2020 01:55:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584842108; bh=y3EnSon9cHSyFeKk+MXsTsrqN7tBu+/NvqQ0fsNxXMc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=utpH1Jcdf6McO64bgE8aonH6Pq6Bj3FQi6pekOzmJuHssYTYA9Xnlolj3ekjYB/5h JtifYKM40AlcaHiZwwDebMUgT4SXUwIVABC4vDaoptou09J0a5xYouAQNQ95zPACOs XUcXINCPsVQwqYCpQXe4ByzOZ6hbZ6bj/v5dVDmU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727944AbgCVBzI (ORCPT ); Sat, 21 Mar 2020 21:55:08 -0400 Received: from mail.kernel.org ([198.145.29.99]:55984 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726409AbgCVBzH (ORCPT ); Sat, 21 Mar 2020 21:55:07 -0400 Received: from localhost (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8E7FD20753; Sun, 22 Mar 2020 01:55:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584842107; bh=y3EnSon9cHSyFeKk+MXsTsrqN7tBu+/NvqQ0fsNxXMc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=odWTk07iZnPjyJTf8Zt9SPHmShEdhbr2Kaz49KSfdgNJy3osLvzpzmrGGoI4/UoSQ TLaPsYC95wVPTJNLKMLZoQK9FYofexYDtt3NFFrHQHvvcBgsbWNqo974bfL9DttjmG rMmNz8y2mXoxzJmNRxTguRw+jkds1cRZ8+YYHQoQ= Date: Sat, 21 Mar 2020 21:55:00 -0400 From: Sasha Levin To: Nathan Chancellor Cc: Ben Hutchings , Greg Kroah-Hartman , Sasha Levin , stable Subject: Re: [stable] locks: fix a potential use-after-free problem when wakeup a waiter Message-ID: <20200322015500.GM4189@sasha-vm> References: <2082b1e11fdbf3b64f0da022fb15a8b615c3678c.camel@codethink.co.uk> <20200318222906.GJ4189@sasha-vm> <20200319063742.GB3274814@kroah.com> <500c8174c171378e8b6802ad70b4bf5563b3fab0.camel@codethink.co.uk> <20200320054130.GA9611@ubuntu-m2-xlarge-x86> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20200320054130.GA9611@ubuntu-m2-xlarge-x86> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Thu, Mar 19, 2020 at 10:41:30PM -0700, Nathan Chancellor wrote: >On Thu, Mar 19, 2020 at 07:27:56PM +0000, Ben Hutchings wrote: >> On Thu, 2020-03-19 at 07:37 +0100, Greg Kroah-Hartman wrote: >> > On Wed, Mar 18, 2020 at 06:29:06PM -0400, Sasha Levin wrote: >> > > On Wed, Mar 18, 2020 at 10:09:20PM +0000, Ben Hutchings wrote: >> > > > This commit (included in 5.6-rc5) seems to be needed for 5.4 and 5.5 >> > > > branches: >> > > > >> > > > commit 6d390e4b5d48ec03bb87e63cf0a2bff5f4e116da >> > > > Author: yangerkun >> > > > Date: Wed Mar 4 15:25:56 2020 +0800 >> > > > >> > > > locks: fix a potential use-after-free problem when wakeup a waiter >> > > >> > > I've queued it up for 5.5 and 5.4, thanks! >> > > >> > > > I'm a bit surprised that it hasn't yet been applied, while some fixes >> > > > from 5.6-rc6 have. >> > > >> > > Greg, I wonder if it makes sense to have you push a "Greg is here >> > > --->" "bookmark" in the form of a tag/branch on linux-stable-rc.git? at >> > > the very least it'll make it easy to see if something was missed or >> > > still waiting in the queue. >> > >> > To quote Jeff Layton: >> > >> > Hi Greg, there is a performance regression with this patch. We're >> > sorting through potential ways to address it at the moment, but you may >> > want to hold off until we have a fix for that merged. >> > >> > Sorry for the hassle! >> > >> > Which is why I dropped it for now. >> > >> > I'll go drop it again :) >> >> I didn't see any mention of this on the stable list though. >> I also don't think that a performance regression outweighs the >> seriousness of the bug being fixed. >> >> Ben. >> > >Looks like a fix for the performance regression was committed yesterday >to mainline. > >dcf23ac3e846c ("locks: reinstate locks_delete_block optimization") I've queued both 6d390e4b5d48 and dcf23ac3e846c to 5.5 and 5.4. -- Thanks, Sasha