From cf2289f2137faad23a0cd663529e9157a5ee4432 Mon Sep 17 00:00:00 2001
From: Michal Privoznik <mprivozn@redhat.com>
Date: Thu, 15 Jan 2015 15:42:04 +0100
Subject: [PATCH] virNetworkDefUpdateIPDHCPHost: Don't crash when updating
 network

https://bugzilla.redhat.com/show_bug.cgi?id=1182486

When updating a network and adding new ip-dhcp-host entry, the deamon
may crash. The problem is, we iterate over existing <host/> entries
trying to compare MAC addresses to see if there's already an existing
rule. However, not all entries are required to have MAC address. For
instance, the following is perfectly valid entry:

<host id='00:04:58:fd:e4:15:1b:09:4c:0e:09:af:e4:d3:8c:b8:ca:1e'
name='redhatipv6.redhat.com' ip='2001:db8:ca2:2::119'/>

When the checking loop iterates over this, the entry's MAC address is
accessed directly. Well, the fix is obvious - check if the address is
defined before trying to compare it.

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
(cherry picked from commit 7d3ae359db604f6052247ad49d7fbce1db7ef99c)
---
 src/conf/network_conf.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/conf/network_conf.c b/src/conf/network_conf.c
index 57e7cec6b9..cac12c4d47 100644
--- a/src/conf/network_conf.c
+++ b/src/conf/network_conf.c
@@ -3486,7 +3486,7 @@ virNetworkDefUpdateIPDHCPHost(virNetworkDefPtr def,
         /* search for the entry with this (ip|mac|name),
          * and update the IP+(mac|name) */
         for (i = 0; i < ipdef->nhosts; i++) {
-            if ((host.mac &&
+            if ((host.mac && ipdef->hosts[i].mac &&
                  !virMacAddrCompare(host.mac, ipdef->hosts[i].mac)) ||
                 (VIR_SOCKET_ADDR_VALID(&host.ip) &&
                  virSocketAddrEqual(&host.ip, &ipdef->hosts[i].ip)) ||
@@ -3521,7 +3521,7 @@ virNetworkDefUpdateIPDHCPHost(virNetworkDefPtr def,
 
         /* log error if an entry with same name/address/ip already exists */
         for (i = 0; i < ipdef->nhosts; i++) {
-            if ((host.mac &&
+            if ((host.mac && ipdef->hosts[i].mac &&
                  !virMacAddrCompare(host.mac, ipdef->hosts[i].mac)) ||
                 (host.name &&
                  STREQ_NULLABLE(host.name, ipdef->hosts[i].name)) ||
@@ -3550,7 +3550,7 @@ virNetworkDefUpdateIPDHCPHost(virNetworkDefPtr def,
 
         /* find matching entry - all specified attributes must match */
         for (i = 0; i < ipdef->nhosts; i++) {
-            if ((!host.mac ||
+            if ((!host.mac || !ipdef->hosts[i].mac ||
                  !virMacAddrCompare(host.mac, ipdef->hosts[i].mac)) &&
                 (!host.name ||
                  STREQ_NULLABLE(host.name, ipdef->hosts[i].name)) &&