From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933702AbaGWU5T (ORCPT ); Wed, 23 Jul 2014 16:57:19 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:58749 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933267AbaGWU5Q (ORCPT ); Wed, 23 Jul 2014 16:57:16 -0400 Date: Wed, 23 Jul 2014 13:57:14 -0700 From: Andrew Morton To: David Rientjes Cc: Sasha Levin , Heiko Carstens , linux-fsdevel , Al Viro , Jan Kara , Dave Jones , LKML , Linus Torvalds Subject: Re: fs: use after free in /proc/pid/mountinfo Message-Id: <20140723135714.54b97f8184ae69ba9fb32228@linux-foundation.org> In-Reply-To: References: <53B3F331.7090204@oracle.com> <53B4CAB8.5070407@oracle.com> <53B6C051.2060704@oracle.com> <20140706100420.GB3589@osiris> <20140709142406.GA27561@osiris> <20140709133138.c523aa03883be5417a4d19a4@linux-foundation.org> <53BDBDE7.8090600@oracle.com> <20140709155939.48b126f891132370532cb999@linux-foundation.org> <53C53223.5040502@oracle.com> X-Mailer: Sylpheed 3.2.0beta5 (GTK+ 2.24.10; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 15 Jul 2014 16:01:34 -0700 (PDT) David Rientjes wrote: > On Tue, 15 Jul 2014, Sasha Levin wrote: > > > I've been running mainline for a while, and while I can reproduce a different > > bug for Hugh, I can't reproduce this one at all. Not sure how to call it now, > > maybe memory corruption from somewhere else (I did find an unrelated memory > > corruption couple days ago)? > > > > I have a very large /proc/pid/mountinfo on one of my busy systems with VM > and slub debugging enabled and have not been able to reproduce the issue > while reading it in a loop for 24 hours. I would call the patch good on > that basis, but it's very strange you'd report this problem a day after > the patch was merged and could not reproduce it once it was reverted. > (Unless the patch was misapplied locally and reapplying it now worked, but > I doubt you originally merged -mm patches into a local tree yourself.) I was going to revert "fs/seq_file: fallback to vmalloc allocation" but the idea of doing that is so lame and pathetic that I think I'll not do that. If we have a bug then let's just find and fix it when someone is able to trigger it.