From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754571AbdCXJrY (ORCPT ); Fri, 24 Mar 2017 05:47:24 -0400 Received: from mail.skyhub.de ([5.9.137.197]:39036 "EHLO mail.skyhub.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751295AbdCXJrO (ORCPT ); Fri, 24 Mar 2017 05:47:14 -0400 Date: Fri, 24 Mar 2017 10:46:56 +0100 From: Borislav Petkov To: Ard Biesheuvel Cc: Ingo Molnar , Dave Young , Baoquan He , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "x86@kernel.org" , "linux-efi@vger.kernel.org" , Thomas Garnier , Kees Cook , Andrew Morton , Masahiro Yamada , Bhupesh Sharma Subject: Re: [PATCH v2] x86/mm/KASLR: EFI region is mistakenly included into KASLR VA space for randomization Message-ID: <20170324094656.r2nln4vbidj5jhqt@pd.tnic> References: <1490331592-31860-1-git-send-email-bhe@redhat.com> <20170324080833.GA15200@gmail.com> <20170324083451.GC30442@x1> <20170324084609.GA6807@dhcp-128-65.nay.redhat.com> <20170324092433.GA3237@gmail.com> <20170324094034.2afxgg43wlezdka5@pd.tnic> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Mar 24, 2017 at 09:42:40AM +0000, Ard Biesheuvel wrote: > That is a different matter. If the regions are only mapped while > runtime services invocations are in progress (as we do on ARM), I am > not sure if it matters that much, given how rarely that occurs in > normal use. Question is, is there anything worth protecting with ASLR or we don't care? I wanna say, we should randomize just in case, especially as it shouldn't be that expensive to do. Also, how does the whole EFI-in-the-kexec-ed-kernel work on ARM? Runtime services get mapped on-demand in the kexec-ed kernel too? -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Borislav Petkov Subject: Re: [PATCH v2] x86/mm/KASLR: EFI region is mistakenly included into KASLR VA space for randomization Date: Fri, 24 Mar 2017 10:46:56 +0100 Message-ID: <20170324094656.r2nln4vbidj5jhqt@pd.tnic> References: <1490331592-31860-1-git-send-email-bhe@redhat.com> <20170324080833.GA15200@gmail.com> <20170324083451.GC30442@x1> <20170324084609.GA6807@dhcp-128-65.nay.redhat.com> <20170324092433.GA3237@gmail.com> <20170324094034.2afxgg43wlezdka5@pd.tnic> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Ard Biesheuvel Cc: Ingo Molnar , Dave Young , Baoquan He , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , "x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Thomas Garnier , Kees Cook , Andrew Morton , Masahiro Yamada , Bhupesh Sharma List-Id: linux-efi@vger.kernel.org On Fri, Mar 24, 2017 at 09:42:40AM +0000, Ard Biesheuvel wrote: > That is a different matter. If the regions are only mapped while > runtime services invocations are in progress (as we do on ARM), I am > not sure if it matters that much, given how rarely that occurs in > normal use. Question is, is there anything worth protecting with ASLR or we don't care? I wanna say, we should randomize just in case, especially as it shouldn't be that expensive to do. Also, how does the whole EFI-in-the-kexec-ed-kernel work on ARM? Runtime services get mapped on-demand in the kexec-ed kernel too? -- Regards/Gruss, Boris. Good mailing practices for 400: avoid top-posting and trim the reply.