From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sowmini Varadhan Subject: Re: [PATCH net-next 2/3] rds: Enable RDS IPv6 support Date: Tue, 26 Jun 2018 06:16:57 -0400 Message-ID: <20180626101657.GA20575@oracle.com> References: <7f4f460079d3d78a18f7d759488048798e99c4db.1529922794.git.ka-cheong.poon@oracle.com> <20180625170317.GA28578@oracle.com> <25e1afda-7497-7f08-815a-286cf775bc09@oracle.com> <20180625175006.GI14823@oracle.com> <43b790c2-8da6-9f18-ae23-ca55388e8b26@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org, santosh.shilimkar@oracle.com, davem@davemloft.net, rds-devel@oss.oracle.com To: Ka-Cheong Poon Return-path: Received: from userp2120.oracle.com ([156.151.31.85]:48268 "EHLO userp2120.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933509AbeFZKRS (ORCPT ); Tue, 26 Jun 2018 06:17:18 -0400 Content-Disposition: inline In-Reply-To: <43b790c2-8da6-9f18-ae23-ca55388e8b26@oracle.com> Sender: netdev-owner@vger.kernel.org List-ID: On (06/26/18 13:30), Ka-Cheong Poon wrote: > > My answer to this is that if a socket is not bound to a link > local address (meaning it is bound to a non-link local address) > and it is used to send to a link local peer, I think it should > fail. Hmm, I'm not sure I agree. I dont think this is forbidden by RFC 6724 - yes, such a packet cannot be forwarded, but if everything is on the same link, and the dest only has a link-local, you should not need to (create and) bind another socket to a link-local to talk to this destination.. > This is consistent with the scope_id check I mentioned in > the previous mail. If the socket is not bound to a link local > address, the bound_scope_id is 0. So if the socket is used to > send to a link local address (which has a non-zero scope_id), the > check will catch it and fail the call. A new conn should not > be created in this case.