From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f41.google.com (mail-wg0-f41.google.com [74.125.82.41]) by kanga.kvack.org (Postfix) with ESMTP id 5122D6B0038 for ; Tue, 25 Nov 2014 05:38:23 -0500 (EST) Received: by mail-wg0-f41.google.com with SMTP id y19so440717wgg.28 for ; Tue, 25 Nov 2014 02:38:22 -0800 (PST) Received: from mx2.suse.de (cantor2.suse.de. [195.135.220.15]) by mx.google.com with ESMTPS id hg6si1371448wjc.36.2014.11.25.02.38.22 for (version=TLSv1 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Tue, 25 Nov 2014 02:38:22 -0800 (PST) Date: Tue, 25 Nov 2014 11:38:20 +0100 From: Michal Hocko Subject: Re: [PATCH 1/5] mm: Introduce OOM kill timeout. Message-ID: <20141125103820.GA4607@dhcp22.suse.cz> References: <201411231349.CAG78628.VFQFOtOSFJMOLH@I-love.SAKURA.ne.jp> <201411231350.DDH78622.LOtOQOFMFSHFJV@I-love.SAKURA.ne.jp> <20141124165032.GA11745@curandero.mameluci.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org List-ID: To: David Rientjes Cc: Tetsuo Handa , linux-mm@kvack.org On Mon 24-11-14 14:29:00, David Rientjes wrote: > On Mon, 24 Nov 2014, Michal Hocko wrote: > > > > The problem described above is one of phenomena which is triggered by > > > a vulnerability which exists since (if I didn't miss something) > > > Linux 2.0 (18 years ago). However, it is too difficult to backport > > > patches which fix the vulnerability. > > > > What is the vulnerability? > > > > There have historically been issues when oom killed processes fail to > exit, so this is probably trying to address one of those issues. Let me clarify. The patch is sold as a security fix. In that context vulnerability means a behavior which might be abused by a user. I was merely interested whether there are some known scenarios which would turn a potential OOM killer deadlock into an exploitable bug. The changelog was rather unclear about it and rather strong in claims that any user might trigger OOM deadlock. -- Michal Hocko SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org