From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5B9C9C43334 for ; Mon, 13 Jun 2022 19:10:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347254AbiFMTKj (ORCPT ); Mon, 13 Jun 2022 15:10:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56070 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346763AbiFMTIG (ORCPT ); Mon, 13 Jun 2022 15:08:06 -0400 Received: from mail-pg1-x533.google.com (mail-pg1-x533.google.com [IPv6:2607:f8b0:4864:20::533]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7ACBD26134 for ; Mon, 13 Jun 2022 10:04:14 -0700 (PDT) Received: by mail-pg1-x533.google.com with SMTP id 129so6092474pgc.2 for ; Mon, 13 Jun 2022 10:04:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=mYjZASrY0U2vsg4+Z3fayp87EJ3UDw4wIJr7nvni9Ek=; b=kNia3fP4ii7v3FKDIFgRBPRWs8JCjCOQhwBs1YRrgihciGcfP3UczdQ1NP3WROY9gc SZq3nrWT95sCnM+OdH/rH54w6vklvee85Zaway/3supSPaXdEbvAZ28Zcq2Eshaug/N/ holljJi3raKp7VZN0MKBK/+0OmDZGbgPymy7Y= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=mYjZASrY0U2vsg4+Z3fayp87EJ3UDw4wIJr7nvni9Ek=; b=do49fy4MyKxNJ1Q0gE5uJEruh+ZphgW5Zhwa7C/Hyli8A1pRHZtq+TOAupFmtzO/yK 4Yh3CtZbFi5Meo6uLEFTw7ZRI8Tef1Jc1M5C+45jl1b/E6LDkSDZSSEHDHahL8434BOU /ApB3FFVROQj4Zd02J0YPuKIYSn7u/eSAWmUvdnWzY7v96rPojQ7zLT/wjnt8K/owRt/ kZ1Hmv/PQ+D33pzYGRfIyH1TaPDo/DHxqbgjgZdCblTw9t1QZu4XcwJ3nxRZHJ56qVfs cEiok2qQNCYRBdEFNR5fzFbNLk+0HyNAnNnxS4b+WvBQiK8LQDVeN2I6AjNynw4JOGqE b8Wg== X-Gm-Message-State: AOAM533StX8WH7CwVLXe+1txUdgY8/zRnDNYYGy00dHosXKlg2wX+RUa MN/btygeQo8mdp4q4KF2fY0EqA== X-Google-Smtp-Source: ABdhPJxK4IuPlzJj4yZnVw7e7eKF60w/wpE1r9dvdOhFJv4qrE5RYKrR7ZvbsO0AYyeNTkD2MhrnGQ== X-Received: by 2002:a05:6a00:8d3:b0:51e:740f:8d60 with SMTP id s19-20020a056a0008d300b0051e740f8d60mr269277pfu.55.1655139853944; Mon, 13 Jun 2022 10:04:13 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id h30-20020aa79f5e000000b00519cfca8e30sm5615501pfr.209.2022.06.13.10.04.13 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 13 Jun 2022 10:04:13 -0700 (PDT) Date: Mon, 13 Jun 2022 10:04:12 -0700 From: Kees Cook To: Sami Tolvanen Cc: linux-kernel@vger.kernel.org, Josh Poimboeuf , Peter Zijlstra , x86@kernel.org, Catalin Marinas , Will Deacon , Mark Rutland , Nathan Chancellor , Nick Desaulniers , Joao Moreira , Sedat Dilek , Steven Rostedt , linux-hardening@vger.kernel.org, linux-arm-kernel@lists.infradead.org, llvm@lists.linux.dev Subject: Re: [RFC PATCH v3 00/20] KCFI support Message-ID: <202206131001.6BA9933C@keescook> References: <20220610233513.1798771-1-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220610233513.1798771-1-samitolvanen@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jun 10, 2022 at 04:34:53PM -0700, Sami Tolvanen wrote: > KCFI is a proposed forward-edge control-flow integrity scheme for > Clang, which is more suitable for kernel use than the existing CFI > scheme used by CONFIG_CFI_CLANG. KCFI doesn't require LTO, doesn't > alter function references to point to a jump table, and won't break > function address equality. The latest LLVM patch is here: > > https://reviews.llvm.org/D119296 > > This RFC series replaces the current arm64 CFI implementation with > KCFI and adds support for x86_64. I think the "RFC" prefix for this series can be dropped. :) It looks to me like all of Peter's concerns have been addressed. I'd say let's get the Clang side landed, and once that's done, land this via x86 -tip? Peter and Will does this sound right to you? It touches arm64, so if -tip isn't okay, I could take it in one of my trees? -- Kees Cook