From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753373Ab0DVD32 (ORCPT ); Wed, 21 Apr 2010 23:29:28 -0400 Received: from mail-qy0-f179.google.com ([209.85.221.179]:58149 "EHLO mail-qy0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752639Ab0DVD31 (ORCPT ); Wed, 21 Apr 2010 23:29:27 -0400 MIME-Version: 1.0 Date: Wed, 21 Apr 2010 20:29:25 -0700 X-Google-Sender-Auth: f0cdc17fa41408db Message-ID: Subject: [PATCH] net: change recvform to return same address length as getsockname on unnamed unix sockets From: Pavel Pergamenshchik To: netdev@vger.kernel.org, davem@davemloft.net Cc: linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org unix_*_recvmsg() returns zero-length sockaddr if the sender is an unnamed AF_UNIX socket. Change it to return a two-byte sockaddr with just the address family, to be consistent with unix_getname(). Signed-off-by: Pavel Pergamenshchik --- Minimal example at http://xzrq.net/uaddrwtf.c Solaris/OS X print 16 and 16. Linux prints 0 and 2 as described above. --- a/net/unix/af_unix.c 2010-04-01 16:02:33.000000000 -0700 +++ b/net/unix/af_unix.c 2010-04-21 20:17:43.564703748 -0700 @@ -1634,9 +1634,13 @@ static void unix_copy_addr(struct msghdr *msg, struct sock *sk) { struct unix_sock *u = unix_sk(sk); + struct sockaddr_un *sunaddr; - msg->msg_namelen = 0; - if (u->addr) { + if (!u->addr) { + msg->msg_namelen = sizeof(short); + sunaddr = msg->msg_name; + sunaddr->sun_family = AF_UNIX; + } else { msg->msg_namelen = u->addr->len; memcpy(msg->msg_name, u->addr->name, u->addr->len); }