From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932108Ab0CXPI0 (ORCPT ); Wed, 24 Mar 2010 11:08:26 -0400 Received: from mx1.redhat.com ([209.132.183.28]:55072 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756480Ab0CXPIY (ORCPT ); Wed, 24 Mar 2010 11:08:24 -0400 Date: Wed, 24 Mar 2010 20:35:39 +0530 From: Amit Shah To: Alan Cox Cc: Benjamin Herrenschmidt , Greg Kroah-Hartman , Linus Torvalds , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Rusty Russell Subject: Re: [PATCH 4/7] hvc_console: Fix race between hvc_close and hvc_remove Message-ID: <20100324150538.GA18581@amit-x200.redhat.com> References: <20100319151326.GC8541@kroah.com> <1269011916-8836-4-git-send-email-gregkh@suse.de> <1269119079.8599.65.camel@pasglop> <20100324113721.008d343e@lxorguk.ukuu.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20100324113721.008d343e@lxorguk.ukuu.org.uk> User-Agent: Mutt/1.5.19 (2009-01-05) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On (Wed) Mar 24 2010 [11:37:21], Alan Cox wrote: > On Sun, 21 Mar 2010 08:04:39 +1100 > Benjamin Herrenschmidt wrote: > > > On Fri, 2010-03-19 at 08:18 -0700, Greg Kroah-Hartman wrote: > > > From: Amit Shah > > > > > > Alan pointed out a race in the code where hvc_remove is invoked. The > > > recent virtio_console work is the first user of hvc_remove(). > > > > This causes hangs during boot on pseries machines. Haven't had a chance > > to track that down yet, but please revert > > e74d098c66543d0731de62eb747ccd5b636a6f4c for now. > > Its an exploitable hole so we should revert both the bug fix *and* the > submission of the virtio console that makes the flaw triggerable, not jus > tthe security fix. If a fix isn't found in reasonable time, I will send a patch that disables hot-unplug of virtio-console ports. Amit From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by ozlabs.org (Postfix) with ESMTP id 2EAEBB7CF5 for ; Thu, 25 Mar 2010 02:08:19 +1100 (EST) Date: Wed, 24 Mar 2010 20:35:39 +0530 From: Amit Shah To: Alan Cox Subject: Re: [PATCH 4/7] hvc_console: Fix race between hvc_close and hvc_remove Message-ID: <20100324150538.GA18581@amit-x200.redhat.com> References: <20100319151326.GC8541@kroah.com> <1269011916-8836-4-git-send-email-gregkh@suse.de> <1269119079.8599.65.camel@pasglop> <20100324113721.008d343e@lxorguk.ukuu.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20100324113721.008d343e@lxorguk.ukuu.org.uk> Cc: Greg Kroah-Hartman , Rusty Russell , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org, Linus Torvalds List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On (Wed) Mar 24 2010 [11:37:21], Alan Cox wrote: > On Sun, 21 Mar 2010 08:04:39 +1100 > Benjamin Herrenschmidt wrote: > > > On Fri, 2010-03-19 at 08:18 -0700, Greg Kroah-Hartman wrote: > > > From: Amit Shah > > > > > > Alan pointed out a race in the code where hvc_remove is invoked. The > > > recent virtio_console work is the first user of hvc_remove(). > > > > This causes hangs during boot on pseries machines. Haven't had a chance > > to track that down yet, but please revert > > e74d098c66543d0731de62eb747ccd5b636a6f4c for now. > > Its an exploitable hole so we should revert both the bug fix *and* the > submission of the virtio console that makes the flaw triggerable, not jus > tthe security fix. If a fix isn't found in reasonable time, I will send a patch that disables hot-unplug of virtio-console ports. Amit