From owner-freebsd-security Sun May 9 6:13:42 1999 Delivered-To: freebsd-security@freebsd.org Received: from verdi.nethelp.no (verdi.nethelp.no [158.36.41.162]) by hub.freebsd.org (Postfix) with SMTP id 70CF11548B for ; Sun, 9 May 1999 06:13:36 -0700 (PDT) (envelope-from sthaug@nethelp.no) Received: (qmail 66939 invoked by uid 1001); 9 May 1999 13:13:35 +0000 (GMT) To: Don.Lewis@tsc.tdk.com Cc: wes@softweyr.com, toasty@HOME.DRAGONDATA.COM, security@FreeBSD.ORG Subject: Re: KKIS.05051999.003b From: sthaug@nethelp.no In-Reply-To: Your message of "Sun, 9 May 1999 06:08:49 -0700" References: <199905091308.GAA20692@salsa.gv.tsc.tdk.com> X-Mailer: Mew version 1.05+ on Emacs 19.34.2 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Date: Sun, 09 May 1999 15:13:34 +0200 Message-ID: <66937.926255614@verdi.nethelp.no> Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > } - The client is asking for messages with zero iov's, and length 0. To > } me, this means it shouldn't receive *anything* (file descriptors or > } otherwise). But the program included below, slightly modified from the > } client() routine, receives one message of length zero. The same thing > } happens on for instance NetBSD 1.4-BETA or NetBSD 1.3.2. Does this mean > } the semantics of receiving zero length messages aren't sufficiently > } well defined? > > I believe the length refers to the length of any data that might > accompany the descriptors. It should be OK to specify a length of 0. > Even if the server was sending data in its reply, I believe it would > not be an error to specify a zero length buffer. The data would just > be truncated to fit the buffer size. Okay, but why should the *standalone* version of the client receive any message at all (which it does: a zero length message) when there's no sender involved at all? Steinar Haug, Nethelp consulting, sthaug@nethelp.no To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message