From 877361d3c01f7f078bc3a9a91854e329f23a7f11 Mon Sep 17 00:00:00 2001
From: Franco Fichtner <franco@opnsense.org>
Date: Wed, 12 Feb 2020 09:33:36 +0100
Subject: [PATCH] dhcp: guard against primary address grab fail

---
 src/etc/inc/plugins.inc.d/dhcpd.inc | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/src/etc/inc/plugins.inc.d/dhcpd.inc b/src/etc/inc/plugins.inc.d/dhcpd.inc
index 3a98af2b9..ea521cfa3 100644
--- a/src/etc/inc/plugins.inc.d/dhcpd.inc
+++ b/src/etc/inc/plugins.inc.d/dhcpd.inc
@@ -497,14 +497,22 @@ function dhcpd_radvd_configure($verbose = false, $blacklist = array())
         }
 
         foreach (config_read_array('virtualip', 'vip') as $vip) {
-            if ($vip['interface'] == $if && is_ipaddrv6($vip['subnet'])) {
-                $subnetv6 = gen_subnetv6($vip['subnet'], $vip['subnet_bits']);
-                $radvdconf .= "\tprefix {$subnetv6}/{$vip['subnet_bits']} {\n";
-                $radvdconf .= "\t\tDeprecatePrefix on;\n";
-                $radvdconf .= "\t\tAdvOnLink on;\n";
-                $radvdconf .= "\t\tAdvAutonomous on;\n";
-                $radvdconf .= "\t};\n";
+            if ($vip['interface'] != $if || !is_ipaddrv6($vip['subnet'])) {
+                continue;
             }
+
+            $subnetv6 = gen_subnetv6($vip['subnet'], $vip['subnet_bits']);
+            $vipnetv6 = "{$subnetv6}/{$vip['subnet_bits']}";
+
+            if ($vipnetv6 == $networkv6) {
+                continue;
+            }
+
+            $radvdconf .= "\tprefix {$vipnetv6} {\n";
+            $radvdconf .= "\t\tDeprecatePrefix on;\n";
+            $radvdconf .= "\t\tAdvOnLink on;\n";
+            $radvdconf .= "\t\tAdvAutonomous on;\n";
+            $radvdconf .= "\t};\n";
         }
 
         if (count($dnslist) > 0) {