From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thomas Haller Subject: [PATCH iproute2] ip-address: properly display zero IPv4 peer address Date: Thu, 22 Oct 2015 10:34:28 +0200 Message-ID: <1445502868-29474-1-git-send-email-thaller@redhat.com> Cc: Thomas Haller To: netdev@vger.kernel.org Return-path: Received: from mx1.redhat.com ([209.132.183.28]:39057 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751523AbbJVIed (ORCPT ); Thu, 22 Oct 2015 04:34:33 -0400 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 4DABCC075D95 for ; Thu, 22 Oct 2015 08:34:33 +0000 (UTC) Sender: netdev-owner@vger.kernel.org List-ID: Kernel allows for zero IPv4 peer addresses (IFA_ADDRESS): ip address add 192.168.5.1 peer 0.0.0.0/24 dev dummy which is distinct from a usual address like: ip address add 192.168.5.1/24 dev dummy ip address add 192.168.5.1 peer 192.168.5.1/24 dev dummy For IPv4, a missing IFA_ADDRESS attribute means that the peer is 0.0.0.0. See inet_fill_ifaddr(), which does: if ((ifa->ifa_address && nla_put_in_addr(skb, IFA_ADDRESS, ifa->ifa_address)) || Signed-off-by: Thomas Haller --- ip/ipaddress.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/ip/ipaddress.c b/ip/ipaddress.c index f290205..6fc4520 100644 --- a/ip/ipaddress.c +++ b/ip/ipaddress.c @@ -949,7 +949,8 @@ int print_addrinfo(const struct sockaddr_nl *who, struct nlmsghdr *n, if (!rta_tb[IFA_LOCAL]) rta_tb[IFA_LOCAL] = rta_tb[IFA_ADDRESS]; - if (!rta_tb[IFA_ADDRESS]) + if (!rta_tb[IFA_ADDRESS] && + ifa->ifa_family != AF_INET) rta_tb[IFA_ADDRESS] = rta_tb[IFA_LOCAL]; if (filter.ifindex && filter.ifindex != ifa->ifa_index) @@ -1034,16 +1035,18 @@ int print_addrinfo(const struct sockaddr_nl *who, struct nlmsghdr *n, RTA_DATA(rta_tb[IFA_LOCAL]), abuf, sizeof(abuf))); - if (rta_tb[IFA_ADDRESS] == NULL || + if (rta_tb[IFA_ADDRESS] != NULL && memcmp(RTA_DATA(rta_tb[IFA_ADDRESS]), RTA_DATA(rta_tb[IFA_LOCAL]), ifa->ifa_family == AF_INET ? 4 : 16) == 0) { fprintf(fp, "/%d ", ifa->ifa_prefixlen); } else { fprintf(fp, " peer %s/%d ", - format_host(ifa->ifa_family, - RTA_PAYLOAD(rta_tb[IFA_ADDRESS]), - RTA_DATA(rta_tb[IFA_ADDRESS]), - abuf, sizeof(abuf)), + rta_tb[IFA_ADDRESS] + ? format_host(ifa->ifa_family, + RTA_PAYLOAD(rta_tb[IFA_ADDRESS]), + RTA_DATA(rta_tb[IFA_ADDRESS]), + abuf, sizeof(abuf)) + : "0.0.0.0", ifa->ifa_prefixlen); } } -- 2.4.3