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Harding" , kernel-hardening@lists.openwall.com, Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] powerpc/32: Stop printing the virtual memory layout Message-ID: <20200305205054.GD6506@cisco> References: <202003021038.8F0369D907@keescook> <20200305150837.835083-1-nivedita@alum.mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200305150837.835083-1-nivedita@alum.mit.edu> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 05, 2020 at 10:08:37AM -0500, Arvind Sankar wrote: > For security, don't display the kernel's virtual memory layout. > > Kees Cook points out: > "These have been entirely removed on other architectures, so let's > just do the same for ia32 and remove it unconditionally." > > 071929dbdd86 ("arm64: Stop printing the virtual memory layout") > 1c31d4e96b8c ("ARM: 8820/1: mm: Stop printing the virtual memory layout") > 31833332f798 ("m68k/mm: Stop printing the virtual memory layout") > fd8d0ca25631 ("parisc: Hide virtual kernel memory layout") > adb1fe9ae2ee ("mm/page_alloc: Remove kernel address exposure in free_reserved_area()") > > Signed-off-by: Arvind Sankar Acked-by: Tycho Andersen 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=-5.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 98EEBC3F2D2 for ; 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Thu, 05 Mar 2020 12:51:01 -0800 (PST) Received: from cisco ([2607:fb90:17d4:133:1002:9a44:e2a2:4464]) by smtp.gmail.com with ESMTPSA id d203sm10941125ywc.29.2020.03.05.12.50.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 05 Mar 2020 12:51:00 -0800 (PST) Date: Thu, 5 Mar 2020 13:50:54 -0700 From: Tycho Andersen To: Arvind Sankar Subject: Re: [PATCH] powerpc/32: Stop printing the virtual memory layout Message-ID: <20200305205054.GD6506@cisco> References: <202003021038.8F0369D907@keescook> <20200305150837.835083-1-nivedita@alum.mit.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200305150837.835083-1-nivedita@alum.mit.edu> User-Agent: Mutt/1.10.1 (2018-07-13) X-Mailman-Approved-At: Fri, 06 Mar 2020 10:00:05 +1100 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Kees Cook , kernel-hardening@lists.openwall.com, linux-kernel@vger.kernel.org, Paul Mackerras , linuxppc-dev@lists.ozlabs.org, "Tobin C . Harding" Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Thu, Mar 05, 2020 at 10:08:37AM -0500, Arvind Sankar wrote: > For security, don't display the kernel's virtual memory layout. > > Kees Cook points out: > "These have been entirely removed on other architectures, so let's > just do the same for ia32 and remove it unconditionally." > > 071929dbdd86 ("arm64: Stop printing the virtual memory layout") > 1c31d4e96b8c ("ARM: 8820/1: mm: Stop printing the virtual memory layout") > 31833332f798 ("m68k/mm: Stop printing the virtual memory layout") > fd8d0ca25631 ("parisc: Hide virtual kernel memory layout") > adb1fe9ae2ee ("mm/page_alloc: Remove kernel address exposure in free_reserved_area()") > > Signed-off-by: Arvind Sankar Acked-by: Tycho Andersen