Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 4 Oct 2001 12:01:51 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 4 Oct 2001 12:01:43 -0400 Received: from vindaloo.ras.ucalgary.ca ([136.159.55.21]:57730 "EHLO vindaloo.ras.ucalgary.ca") by vger.kernel.org with ESMTP id ; Thu, 4 Oct 2001 12:01:36 -0400 Date: Thu, 4 Oct 2001 10:02:00 -0600 Message-Id: <200110041602.f94G20k06280@vindaloo.ras.ucalgary.ca> From: Richard Gooch To: Linus Torvalds Cc: "Eric W. Biederman" , Subject: Re: Security question: "Text file busy" overwriting executables but not shared libraries? In-Reply-To: In-Reply-To:

Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Linus Torvalds writes: > > On 4 Oct 2001, Eric W. Biederman wrote: > > > > First what user space really wants is the MAP_COPY. Which is > > MAP_PRIVATE with the guarantee that they don't see anyone else's changes. > > Which is a completely idiotic idea, and which is only just another > example of how absolutely and stunningly _stupid_ Hurd is. Indeed. If you're updated a shared library, why not *create a new file* and then rename it?!? That lets running programmes work fine, and new programmes will get the new library. Also, the following construct makes a lot of sense: ld -shared -o libfred.so *.o || mv libfred.so /usr/local/lib Why? Because if ld(1) fails for some reason, and ends up writing a short file, *you don't want to install the bloody thing*!!! Any new user would be stuffed (no way around that, even with MAP_COPY). I don't want to install/upgrade to a half-working library. What's the point in that? Regards, Richard.... Permanent: rgooch@atnf.csiro.au Current: rgooch@ras.ucalgary.ca - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/