Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759286AbeAIToN (ORCPT + 1 other); Tue, 9 Jan 2018 14:44:13 -0500 Received: from mail-ot0-f196.google.com ([74.125.82.196]:42496 "EHLO mail-ot0-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759163AbeAIToH (ORCPT ); Tue, 9 Jan 2018 14:44:07 -0500 X-Google-Smtp-Source: ACJfBos+tNRlnOI+f/Rk2bAhWZ0j//H7LVbJQNF09bjpSGnFh5hvJvZxZ8je8rOGPBJXIYEMa2GXv2KIMThoXcUjq2I= MIME-Version: 1.0 In-Reply-To: References: <151520099201.32271.4677179499894422956.stgit@dwillia2-desk3.amr.corp.intel.com> From: Dan Williams Date: Tue, 9 Jan 2018 11:44:05 -0800 Message-ID: Subject: Re: [PATCH 00/18] prevent bounds-check bypass via speculative execution To: Jiri Kosina Cc: Linux Kernel Mailing List , Mark Rutland , Peter Zijlstra , Alan Cox , Srinivas Pandruvada , Will Deacon , Solomon Peachy , "H. Peter Anvin" , Christian Lamparter , Elena Reshetova , linux-arch@vger.kernel.org, Andi Kleen , "James E.J. Bottomley" , linux-scsi , Jonathan Corbet , X86 ML , Ingo Molnar , Alexey Kuznetsov , Zhang Rui , "Linux-media@vger.kernel.org" , Arnd Bergmann , Jan Kara , Eduardo Valentin , Al Viro , qla2xxx-upstream@qlogic.com, Thomas Gleixner , Mauro Carvalho Chehab , Arjan van de Ven , Kalle Valo , Alan Cox , "Martin K. Petersen" , Hideaki YOSHIFUJI , Greg KH , linux-wireless@vger.kernel.org, "Eric W. Biederman" , Netdev , Linus Torvalds , "David S. Miller" , Laurent Pinchart Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Tue, Jan 9, 2018 at 11:34 AM, Jiri Kosina wrote: > On Fri, 5 Jan 2018, Dan Williams wrote: > > [ ... snip ... ] >> Andi Kleen (1): >> x86, barrier: stop speculation for failed access_ok >> >> Dan Williams (13): >> x86: implement nospec_barrier() >> [media] uvcvideo: prevent bounds-check bypass via speculative execution >> carl9170: prevent bounds-check bypass via speculative execution >> p54: prevent bounds-check bypass via speculative execution >> qla2xxx: prevent bounds-check bypass via speculative execution >> cw1200: prevent bounds-check bypass via speculative execution >> Thermal/int340x: prevent bounds-check bypass via speculative execution >> ipv6: prevent bounds-check bypass via speculative execution >> ipv4: prevent bounds-check bypass via speculative execution >> vfs, fdtable: prevent bounds-check bypass via speculative execution >> net: mpls: prevent bounds-check bypass via speculative execution >> udf: prevent bounds-check bypass via speculative execution >> userns: prevent bounds-check bypass via speculative execution >> >> Mark Rutland (4): >> asm-generic/barrier: add generic nospec helpers >> Documentation: document nospec helpers >> arm64: implement nospec_ptr() >> arm: implement nospec_ptr() > > So considering the recent publication of [1], how come we all of a sudden > don't need the barriers in ___bpf_prog_run(), namely for LD_IMM_DW and > LDX_MEM_##SIZEOP, and something comparable for eBPF JIT? > > Is this going to be handled in eBPF in some other way? > > Without that in place, and considering Jann Horn's paper, it would seem > like PTI doesn't really lock it down fully, right? Here is the latest (v3) bpf fix: https://patchwork.ozlabs.org/patch/856645/ I currently have v2 on my 'nospec' branch and will move that to v3 for the next update, unless it goes upstream before then.