Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760850AbaGOX5E (ORCPT ); Tue, 15 Jul 2014 19:57:04 -0400 Received: from mail-vc0-f179.google.com ([209.85.220.179]:35488 "EHLO mail-vc0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757837AbaGOX46 (ORCPT ); Tue, 15 Jul 2014 19:56:58 -0400 MIME-Version: 1.0 In-Reply-To: <20140715235212.GC32651@kroah.com> References: <20140715235212.GC32651@kroah.com> From: Andrew Lutomirski Date: Tue, 15 Jul 2014 16:56:36 -0700 Message-ID: Subject: Re: DO NOT APPLY: x86-64, espfix: Don't leak bits 31:16 of %esp returning to 16-bit stack To: Greg KH Cc: Kamal Mostafa , "linux-kernel@vger.kernel.org" , stable , kernel-team@lists.ubuntu.com, "H. Peter Anvin" , Konrad Rzeszutek Wilk , Borislav Petkov , Linus Torvalds , Dirk Hohndel , Arjan van de Ven , comex , Alexander van Heukelum , Boris Ostrovsky Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 15, 2014 at 4:52 PM, Greg KH wrote: > On Tue, Jul 15, 2014 at 04:21:46PM -0700, Andrew Lutomirski wrote: >> On Tue, Jul 15, 2014 at 2:28 PM, Kamal Mostafa wrote: >> > 3.13.11.5 -stable review patch. If anyone has any objections, please let me know. >> > >> > ------------------ >> > >> > From: "H. Peter Anvin" >> > >> > commit 3891a04aafd668686239349ea58f3314ea2af86b upstream. >> >> Do not apply to any -stable release yet. This causes nasty regressions on Xen. > > I thought you all found the Xen-regression-fix patch a few hours ago, > right? That patch is insufficient: Xen guests still fail to initialize espfix64 correctly on SMP. It's currently unclear that espfix64 can work at all on Xen -- it's may be rather fundamentally incompatible with the Xen hypercall IRET mechanism. So it might need to be disabled entirely on Xen (and maybe Xen will fix the info leak in the hypervisor). > > This means that Linus's tree is also broken? Yes. --Andy -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/