From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alan Cox Subject: Re: [PATCH] linux 2.9.10-rc1: Fix oops in unix_dgram_sendmsg when using SELinux and SOCK_SEQPACKET Date: Thu, 18 Nov 2004 16:45:14 +0000 Message-ID: <1100796294.6019.8.camel@localhost.localdomain> References: Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Cc: Ross Kendall Axe , netdev@oss.sgi.com, Stephen Smalley , lkml , Chris Wright , "David S. Miller" Return-path: To: James Morris In-Reply-To: Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org On Iau, 2004-11-18 at 03:42, James Morris wrote: > > Well, my reading of socket(2) suggests that it's _not_ supposed to work. > > sendto() on a non connected socket should fail with ENOTCONN. Not entirely true at all. A network protocol can implement lazy binding and do implicit binding on the sendto. Other protocols might not actually have a receiving component so have no bind() functionality at all. > According to the send(2) man page, we may return EISCONN if the address > and addr length are not NULL and zero. I think that the man page is > incorrect. Posix says that EISCONN means "A destination address was > specified and the socket is already connected", not "A destination address > was specified and the socket is connected mode". i.e. we should only > return EISCONN if the socket is in a connected state. POSIX 1003.1g draft 6.4 permits a user to pass a "null" address for various things. Indeed some systems implement send() as sendto() with a NULL, 0 address component and some user space does likewise. It also has a lot to say on the other cases although I don't think it ever fully got past draft state. You also want to look at TCP/IP illustrated to see some of the assumptions handed down from on high by BSD and which should not be broken.