From owner-freebsd-security Mon Oct 13 18:29:42 1997 Return-Path: Received: (from root@localhost) by hub.freebsd.org (8.8.7/8.8.7) id SAA09582 for security-outgoing; Mon, 13 Oct 1997 18:29:42 -0700 (PDT) (envelope-from owner-freebsd-security) Received: from henry.cs.adfa.oz.au (henry.cs.adfa.oz.au [131.236.21.158]) by hub.freebsd.org (8.8.7/8.8.7) with ESMTP id SAA09564 for ; Mon, 13 Oct 1997 18:29:26 -0700 (PDT) (envelope-from wkt@henry.cs.adfa.oz.au) Received: (from wkt@localhost) by henry.cs.adfa.oz.au (8.7.5/8.7.3) id LAA09227 for freebsd-security@FreeBSD.ORG; Tue, 14 Oct 1997 11:29:45 +1000 (EST) From: Warren Toomey Message-Id: <199710140129.LAA09227@henry.cs.adfa.oz.au> Subject: Re: Zeroing pages, was Re: C2 Date: Tue, 14 Oct 1997 11:29:45 +1000 (EST) Cc: freebsd-security@FreeBSD.ORG In-Reply-To: <199710140042.RAA16597@usr07.primenet.com> from Terry Lambert at "Oct 14, 97 00:42:39 am" Reply-To: wkt@cs.adfa.oz.au X-Mailer: ELM [version 2.4ME+ PL22 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-freebsd-security@FreeBSD.ORG X-Loop: FreeBSD.org Precedence: bulk In article by Terry Lambert: > > > Basically, we need to purge all memory when it is allocated, or > > > deallocated. > This is interesting. Can you give a small sample program for accessing > data from another program? As far as I know, pages are either filled > from a swap store (and contain data accessable to you) or zero-filled; > I can't think of a way (off the top of my head) to make this not true. > Terry Lambert There's no way of accessing the unused contents of mbufs from user space? Any other kernel buffers? I doubt it, but that's the only other way I can think of. Warren Toomey