From owner-freebsd-arch Sun Jun 30 5:25:54 2002 Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id E015E37B400 for ; Sun, 30 Jun 2002 05:25:51 -0700 (PDT) Received: from gull.mail.pas.earthlink.net (gull.mail.pas.earthlink.net [207.217.120.84]) by mx1.FreeBSD.org (Postfix) with ESMTP id 8C26F43E1D for ; Sun, 30 Jun 2002 05:25:51 -0700 (PDT) (envelope-from tlambert2@mindspring.com) Received: from pool0052.cvx40-bradley.dialup.earthlink.net ([216.244.42.52] helo=mindspring.com) by gull.mail.pas.earthlink.net with esmtp (Exim 3.33 #2) id 17Odlx-0007Tu-00; Sun, 30 Jun 2002 05:25:46 -0700 Message-ID: <3D1EF89E.B5BC0CCE@mindspring.com> Date: Sun, 30 Jun 2002 05:25:02 -0700 From: Terry Lambert X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Cedric Berger Cc: arch@freebsd.org Subject: Re: Time to make the stack non-executable? References: <3D1E28ED.B67A5271@FreeBSD.org> <3D1E3126.C96FFAA5@mindspring.com> <3D1EF628.5090105@wireless-networks.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Cedric Berger wrote: > It is the default (noexec_user_stack) for 64-bit Solaris. > http://docs.sun.com/?q=noexec_user_stack&p=/doc/806-7009/6jftnqsis&a=view > Since I doubt Sun would set a default which makes Java unusable, > It seems to me that Java has a good probability to be OK with that. > Or am I missing something? SPARC != i386. SunSpot uses executable stack on i386, according to one poster. However, this man page reference for Solaris gives a nice clue on how to get around it: explicit use of mprotect() (clever lads!). That actually gets rid of a lot of the objections I was able to come up with, if doing that to the stack would work on FreeBSD as well (seems to on 4.6). That leaves the issue of binary compatability; the sysctl approach (per Solaris) is not a good idea, since you can't stop other processes starting during an off-then-on-then-off window. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message