From owner-freebsd-hackers Wed Sep 9 23:15:36 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id XAA06620 for freebsd-hackers-outgoing; Wed, 9 Sep 1998 23:15:36 -0700 (PDT) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from rover.village.org (rover.village.org [204.144.255.49]) by hub.freebsd.org (8.8.8/8.8.8) with SMTP id XAA06615 for ; Wed, 9 Sep 1998 23:15:33 -0700 (PDT) (envelope-from imp@village.org) Received: from harmony [10.0.0.6] by rover.village.org with esmtp (Exim 1.71 #1) id 0zH00l-0005i8-00; Thu, 10 Sep 1998 00:15:19 -0600 Received: from harmony.village.org (localhost.village.org [127.0.0.1]) by harmony.village.org (8.9.1/8.8.3) with ESMTP id AAA09917 for ; Thu, 10 Sep 1998 00:16:19 -0600 (MDT) Message-Id: <199809100616.AAA09917@harmony.village.org> To: freebsd-hackers@FreeBSD.ORG Subject: Idea re stack and system calls. Date: Thu, 10 Sep 1998 00:16:19 -0600 From: Warner Losh Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hmmmm. Never mind. It turns out that one can execute data fairly trivially, so the "egg" would only need copy part of itself to the start of data and jump to that. Better to make the stack non-executable, which has its own set of problems that have been beaten to death here, so I'll not repeat them. The idea of putting the firewall at the system call location was interesting while it lasted... :-( Warner To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message