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 X-Spam-Level: X-Spam-Status: No, score=-6.9 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1C87CC433DF for ; Tue, 18 Aug 2020 19:46:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ECE9E2076E for ; Tue, 18 Aug 2020 19:46:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="TRDwzjpv" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726718AbgHRTqq (ORCPT ); Tue, 18 Aug 2020 15:46:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45744 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726630AbgHRTqn (ORCPT ); Tue, 18 Aug 2020 15:46:43 -0400 Received: from mail-pj1-x1043.google.com (mail-pj1-x1043.google.com [IPv6:2607:f8b0:4864:20::1043]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BA961C061342 for ; Tue, 18 Aug 2020 12:46:43 -0700 (PDT) Received: by mail-pj1-x1043.google.com with SMTP id kr4so20490pjb.2 for ; Tue, 18 Aug 2020 12:46:43 -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=ylBQHIGj+jC+wMGAW+WiPoCXXWUQK9WgH6fcVkJtSBg=; b=TRDwzjpv9nxBnOSNPospJ+g2+lM26x7LrfAWZDm2gvCsnlrIhyGQMvVZ+nN+hu7WkX O/oo+OEjbZ2O9PmpH/HltGohEtaT4mQAuhz2mTIFpqD9eXrS0bAzADnlvGV+CZhjlU6D 56u72kcTdOBo0I+2qXN79Jwyll3yLdhk3jnEc= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=ylBQHIGj+jC+wMGAW+WiPoCXXWUQK9WgH6fcVkJtSBg=; b=YJdz8tN81AZYgY0HKIEwFosENEshKX2QOv6XtIRnKaHp3W5zrGU8JggYye/XWyiIuy 7kuIReoA0elv/vAAVRko0NbblrXe5cOZjIYYZZE4JSk9e0bEgBzZTfdWCNgRni5IJd6M 72K039zeqQHIwo/k21IT4he88VU/FXywdv+malVA4iIigzIeulo7xmodkwTpRWkSi/zV zXAaAnZ6JNtccCMdxyI1la7gN6KOhcm6Db3KXlv4Cug/l4/09Ab1gAg1Dw62IYlSgOu+ 7lgl0AFh19k5DwRBm0c2UInkM2fP2JT/L9LXexTxfVTaQYEtRjYXy/fzr2iiFgxCZoiT NWhg== X-Gm-Message-State: AOAM532CP41K5nnruv+oFjiiEmD6J95nWqmRJaqU3UWorXvoA3DD4ycz 8Tqhc41WfPw4BsjanpFLus+cpA== X-Google-Smtp-Source: ABdhPJxQpoCNUK9oxMIJWJCcBhsLXV3qhwZ1vk6NlnSPUfnJzoewH/BG+Ra1OO11qvGzKQ2Um0GcDw== X-Received: by 2002:a17:90b:148b:: with SMTP id js11mr1261981pjb.234.1597780003259; Tue, 18 Aug 2020 12:46:43 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id j5sm25754806pfg.80.2020.08.18.12.46.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Aug 2020 12:46:42 -0700 (PDT) Date: Tue, 18 Aug 2020 12:46:41 -0700 From: Kees Cook To: Christoph Hellwig Cc: Al Viro , Michael Ellerman , x86@kernel.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Subject: Re: [PATCH 09/11] x86: remove address space overrides using set_fs() Message-ID: <202008181246.A03BB9CEA@keescook> References: <20200817073212.830069-1-hch@lst.de> <20200817073212.830069-10-hch@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200817073212.830069-10-hch@lst.de> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Aug 17, 2020 at 09:32:10AM +0200, Christoph Hellwig wrote: > Stop providing the possibility to override the address space using > set_fs() now that there is no need for that any more. To properly > handle the TASK_SIZE_MAX checking for 4 vs 5-level page tables on > x86 a new alternative is introduced, which just like the one in > entry_64.S has to use the hardcoded virtual address bits to escape > the fact that TASK_SIZE_MAX isn't actually a constant when 5-level > page tables are enabled. > > Signed-off-by: Christoph Hellwig Awesome. :) Reviewed-by: Kees Cook -- Kees Cook