From owner-freebsd-security Fri Jan 21 22:25: 3 2000 Delivered-To: freebsd-security@freebsd.org Received: from lariat.lariat.org (lariat.lariat.org [206.100.185.2]) by hub.freebsd.org (Postfix) with ESMTP id 72E6914C19 for ; Fri, 21 Jan 2000 22:24:58 -0800 (PST) (envelope-from brett@lariat.org) Received: from workhorse (IDENT:ppp0.lariat.org@lariat.lariat.org [206.100.185.2]) by lariat.lariat.org (8.9.3/8.9.3) with ESMTP id XAA00176; Fri, 21 Jan 2000 23:24:36 -0700 (MST) Message-Id: <4.2.2.20000121231704.01977b60@localhost> X-Sender: brett@localhost X-Mailer: QUALCOMM Windows Eudora Pro Version 4.2.2 Date: Fri, 21 Jan 2000 23:24:36 -0700 To: "Rodney W. Grimes" , keramida@ceid.upatras.gr From: Brett Glass Subject: Re: stream.c worst-case kernel paths Cc: dillon@apollo.backplane.com (Matthew Dillon), imp@village.org (Warner Losh), avalon@coombs.anu.edu.au (Darren Reed), security@FreeBSD.ORG In-Reply-To: <200001220614.WAA59998@gndrsh.dnsmgr.net> References: <20000122044638.B27337@hades.hell.gr> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org At 11:14 PM 1/21/2000 , Rodney W. Grimes wrote: >(Your (a) above is invalid data between the ip layer and tcp, handled at >either output from ip or as input to tcp in the upwards stack direction, >and (c) is output from tcp to ip in the downward stack direction.) Actually, it's invalid data in a LOT of cases. I think that the check should be pushed downward and that the packet source address should be flagged as multicast in the mbuf flags. This could eliminate quite a few tests. Try the command grep IN_MULTICAST /sys/netinet/* | more and you'll see what I mean. (Not all of the tests would be subsumed by this, but many would. There's also a check in /sys/net/if_ethersubr.c.) --Brett To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message