From owner-freebsd-hackers Mon Aug 23 14:47:41 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from mail1.its.rpi.edu (mail1.its.rpi.edu [128.113.100.7]) by hub.freebsd.org (Postfix) with ESMTP id 90C0B14FA1 for ; Mon, 23 Aug 1999 14:47:33 -0700 (PDT) (envelope-from drosih@rpi.edu) Received: from [128.113.24.47] (gilead.acs.rpi.edu [128.113.24.47]) by mail1.its.rpi.edu (8.9.3/8.9.3) with ESMTP id RAA19894; Mon, 23 Aug 1999 17:47:18 -0400 Mime-Version: 1.0 X-Sender: drosih@mail.rpi.edu Message-Id: In-Reply-To: <199908232012.WAA78393@gratis.grondar.za> References: <199908232012.WAA78393@gratis.grondar.za> Date: Mon, 23 Aug 1999 17:47:46 -0400 To: Mark Murray From: Garance A Drosihn Subject: Re: Mandatory locking? Cc: hackers@FreeBSD.ORG Content-Type: text/plain; charset="us-ascii" ; format="flowed" Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG At 10:12 PM +0200 8/23/99, Mark Murray wrote: >Folk are all skirting around a very convenient (and necessary) >loophole; in cases where there _is_ mandatory locking, there >is always some meta-user which is allowed to violate this. If we include non-unix systems in the discussion, this isn't always true. In the mainframe OS that I used to work on, there was no meta-user who could just ignore locks set by other processes. The super-user could find which process had a file locked, and kill that process (thus removing the lock). Or the super-user could run a program which modified the in-core locking table so the file did not appear to be locked. However, ordinary programs run by that super user did not have any magic power to ignore mandatory locks set by some other process. It is true that nobody is running that mainframe OS anymore... :-) I'm just saying we COULD (and maybe "should"?) implement this such that even root has to honor mandatory locks. Root (or some thing) would have a way to get around or cancel the mandatory lock, but "standard" programs run by root should not bypass the mandatory locking. (IMO) --- Garance Alistair Drosehn = gad@eclipse.acs.rpi.edu Senior Systems Programmer or drosih@rpi.edu Rensselaer Polytechnic Institute To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message