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=-3.7 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham 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 1C9E8C282DB for ; Mon, 21 Jan 2019 09:19:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E09BA2084A for ; Mon, 21 Jan 2019 09:19:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1548062372; bh=lv4ARIQuBTY1ywLQfOrPjTpzGR3GgkAR+TPhxv+vGN4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=ZXVaQ5/hEZFbwoemUaWAEYXNImNL+dAchz0fgqco1lbvV571u/mwlw86707pVPnqJ M50guHBfeFYvs8MUDpL8PJDsTk10uWJCy44NjdH3Vzv0wB/D/PWVyLVI9/YTC4ja+W baYLwGgRUtLYhQ2gXLKKp94OYy/CrlJvR4RCZeyU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727599AbfAUJTa (ORCPT ); Mon, 21 Jan 2019 04:19:30 -0500 Received: from mx2.suse.de ([195.135.220.15]:55642 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726044AbfAUJT3 (ORCPT ); Mon, 21 Jan 2019 04:19:29 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 9B76FAD18; Mon, 21 Jan 2019 09:19:28 +0000 (UTC) Date: Mon, 21 Jan 2019 10:19:27 +0100 From: Michal Hocko To: Shakeel Butt Cc: Johannes Weiner , David Rientjes , Andrew Morton , Tetsuo Handa , Roman Gushchin , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH] mm, oom: fix use-after-free in oom_kill_process Message-ID: <20190121091927.GK4087@dhcp22.suse.cz> References: <20190119005022.61321-1-shakeelb@google.com> <20190119070934.GD4087@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190119070934.GD4087@dhcp22.suse.cz> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat 19-01-19 08:09:34, Michal Hocko wrote: [...] > Fixes: 5e9d834a0e0c ("oom: sacrifice child with highest badness score for parent") So I've double checked and I was wrong blaming this commit. Back then it was tasklist_lock to protect us from releasing the task. It's been only since 6b0c81b3be11 ("mm, oom: reduce dependency on tasklist_lock") that we rely on the reference counting and unless I am missing something this is also the commit which has introduced this bug. > Cc: stable -- Michal Hocko SUSE Labs