From owner-freebsd-security Wed Oct 4 22:15:25 2000 Delivered-To: freebsd-security@freebsd.org Received: from static.unixfreak.org (static.unixfreak.org [63.198.170.139]) by hub.freebsd.org (Postfix) with ESMTP id 1734A37B66D for ; Wed, 4 Oct 2000 22:15:22 -0700 (PDT) Received: by static.unixfreak.org (Postfix, from userid 1000) id C907D1F21; Wed, 4 Oct 2000 22:15:21 -0700 (PDT) Subject: Re: BSD chpass (fwd) In-Reply-To: <200010050453.AAA32275@mailer.progressive-comp.com> from Hank Leininger at "Oct 5, 2000 00:53:21 am" To: Hank Leininger Date: Wed, 4 Oct 2000 22:15:21 -0700 (PDT) Cc: freebsd-security@FreeBSD.ORG From: Dima Dorfman Reply-To: dima@unixfreak.org X-Mailer: ELM [version 2.4ME+ PL61 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Message-Id: <20001005051521.C907D1F21@static.unixfreak.org> Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > On 2000-10-05, Dima Dorfman wrote: > > > > On Wed, Oct 04, 2000 at 10:47:15AM -0400, Garrett Wollman wrote: > > > Except you can still just mount a doctored copy over the top of it > > > Actually, now that I think about it, this can be detered to a certain > > point. If you're running with securelevel >= 2, you can't load KLDs, > > and you can't run newfs. What would you mount? A vn device? Nope, > > unless the KLD is already loaded. A floppy? If you have physical > > Perhaps this is a stupid question, but why is mount particularly needed at > high securelevels? So long as unmount(2) can be called by shutdown > scripts. Hm... remounting / ro before halt/reboot perhaps... but perhaps > that behavior could be straightforward-ly special cased? It's not like > mount(2) is a hot path =) And/or, disallow mounts to mount points which > are not regular, empty directories, if securelevel >= 2? What legit uses > (that could not be learned around by an admin) would this break? Disallowing mounts altogether will break on-request mounting of volumes by things like amd(8), which is quite important, IMO. Disallowing mounts on non-empty directories and other "irregular" files is another story. While there are some legitimate uses for this, they are far less common. Regards -- Dima Dorfman Finger dima@unixfreak.org for my public PGP key. "War doesn't determine who's right, it determines who's left." -- Confuscious To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message