From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Howells Subject: Re: [PATCH 26/30] Lock down ftrace Date: Fri, 10 Nov 2017 10:21:44 +0000 Message-ID: <27646.1510309304@warthog.procyon.org.uk> References: <151024863544.28329.2436580122759221600.stgit@warthog.procyon.org.uk> <151024883613.28329.14808632296386937974.stgit@warthog.procyon.org.uk> <27323.1510308432@warthog.procyon.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Return-path: In-Reply-To: Content-ID: <27645.1510309304.1-S6HVgzuS8uM4Awkfq6JHfwNdhmdF6hFW@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jiri Kosina Cc: dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Alexei Starovoitov , linux-security-module-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, gnomes-qBU/x9rampVanCEyBjwyrvXRex20P6io@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, jforbes-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Steven Rostedt List-Id: linux-efi@vger.kernel.org Jiri Kosina wrote: > > The idea is to prevent cryptographic data for filesystems and other things > > from being read out of the kernel memory as well as to prevent unauthorised > > modification of kernel memory. > > Then it would make sense to actually lock down dumping of registers / > function arguments (kprobes can currently do that, ftrace eventually could > as well I guess), but disabling the whole ftrace altogether seems like a > totally unnecessary overkill. That would be fine by me. I have a patch that locks down kprobes in this series. Steven says that ftrace might acquire the ability to dump registers in the future. David From mboxrd@z Thu Jan 1 00:00:00 1970 From: dhowells@redhat.com (David Howells) Date: Fri, 10 Nov 2017 10:21:44 +0000 Subject: [PATCH 26/30] Lock down ftrace In-Reply-To: References: <151024863544.28329.2436580122759221600.stgit@warthog.procyon.org.uk> <151024883613.28329.14808632296386937974.stgit@warthog.procyon.org.uk> <27323.1510308432@warthog.procyon.org.uk> Message-ID: <27646.1510309304@warthog.procyon.org.uk> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org Jiri Kosina wrote: > > The idea is to prevent cryptographic data for filesystems and other things > > from being read out of the kernel memory as well as to prevent unauthorised > > modification of kernel memory. > > Then it would make sense to actually lock down dumping of registers / > function arguments (kprobes can currently do that, ftrace eventually could > as well I guess), but disabling the whole ftrace altogether seems like a > totally unnecessary overkill. That would be fine by me. I have a patch that locks down kprobes in this series. Steven says that ftrace might acquire the ability to dump registers in the future. David -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752514AbdKJKVt convert rfc822-to-8bit (ORCPT ); Fri, 10 Nov 2017 05:21:49 -0500 Received: from mx1.redhat.com ([209.132.183.28]:56052 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751683AbdKJKVr (ORCPT ); Fri, 10 Nov 2017 05:21:47 -0500 Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 From: David Howells In-Reply-To: References: <151024863544.28329.2436580122759221600.stgit@warthog.procyon.org.uk> <151024883613.28329.14808632296386937974.stgit@warthog.procyon.org.uk> <27323.1510308432@warthog.procyon.org.uk> To: Jiri Kosina Cc: dhowells@redhat.com, Alexei Starovoitov , linux-security-module@vger.kernel.org, gnomes@lxorguk.ukuu.org.uk, linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, jforbes@redhat.com, Steven Rostedt Subject: Re: [PATCH 26/30] Lock down ftrace MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <27645.1510309304.1@warthog.procyon.org.uk> Content-Transfer-Encoding: 8BIT Date: Fri, 10 Nov 2017 10:21:44 +0000 Message-ID: <27646.1510309304@warthog.procyon.org.uk> X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.26]); Fri, 10 Nov 2017 10:21:47 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Jiri Kosina wrote: > > The idea is to prevent cryptographic data for filesystems and other things > > from being read out of the kernel memory as well as to prevent unauthorised > > modification of kernel memory. > > Then it would make sense to actually lock down dumping of registers / > function arguments (kprobes can currently do that, ftrace eventually could > as well I guess), but disabling the whole ftrace altogether seems like a > totally unnecessary overkill. That would be fine by me. I have a patch that locks down kprobes in this series. Steven says that ftrace might acquire the ability to dump registers in the future. David