From owner-freebsd-hackers Wed Jul 15 16:06:43 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id QAA01903 for freebsd-hackers-outgoing; Wed, 15 Jul 1998 16:06:43 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from mail.camalott.com (root@mail.camalott.com [208.203.140.2]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id QAA01898 for ; Wed, 15 Jul 1998 16:06:41 -0700 (PDT) (envelope-from joelh@gnu.org) Received: from detlev.UUCP (tex-112.camalott.com [208.229.74.112]) by mail.camalott.com (8.8.7/8.8.5) with ESMTP id SAA05444; Wed, 15 Jul 1998 18:06:49 -0500 Received: (from joelh@localhost) by detlev.UUCP (8.8.8/8.8.8) id SAA15377; Wed, 15 Jul 1998 18:05:58 -0500 (CDT) (envelope-from joelh) Date: Wed, 15 Jul 1998 18:05:58 -0500 (CDT) Message-Id: <199807152305.SAA15377@detlev.UUCP> To: robert+freebsd@cyrus.watson.org CC: matthew@wolfepub.com, hackers@FreeBSD.ORG In-reply-to: (message from Robert Watson on Wed, 15 Jul 1998 17:12:15 -0400 (EDT)) Subject: Re: Protecting data in memory From: Joel Ray Holveck Reply-to: joelh@gnu.org References: Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG >>> Is there any way to protect a programs memory space from all users, even >>> root? >> No. root always has access to all memory space. Consider: If it were >> otherwise, root could just patch the kernel and gain whatever access >> was needed. > On the contrary. This is the purpose of securelevels and read-only > files/file-systems. I realize this. I was actually giving a simplistic example. Yes, you can prevent the kernel from being patched. You would also have to prevent trojan horse attacks elsewhere (ie, r/o /usr and /), not to mention avoid root managing to patch the in-core kernel, etc, etc. Best, joelh -- Joel Ray Holveck - joelh@gnu.org - http://www.wp.com/piquan Fourth law of programming: Anything that can go wrong wi sendmail: segmentation violation - core dumped To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message