From 012e486414c394e506f1c3301f07f24289a5302f Mon Sep 17 00:00:00 2001
From: bergware <bergware@users.noreply.github.com>
Date: Thu, 8 May 2025 23:33:32 +0200
Subject: [PATCH] docker: better handling of IPv6 /128 subnets

---
 etc/rc.d/rc.docker | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/etc/rc.d/rc.docker b/etc/rc.d/rc.docker
index 08c4f43a5..8739014dc 100755
--- a/etc/rc.d/rc.docker
+++ b/etc/rc.d/rc.docker
@@ -356,10 +356,10 @@ docker_network_start(){
         GATEWAY=$(ip -4 route show default dev $NETWORK | awk '{print $3;exit}')
       fi
       SUBNET6=; GATEWAY6=; SERVER6=;
-      [[ -z ${!AUTO} || ${!AUTO} =~ "6" ]] && IPV6=$(ip -6 -br addr show scope global primary -deprecated dev $NETWORK | awk '{print $3;exit}') || IPV6=
+      # get IPv6 address - ignore any /128 networks
+      [[ -z ${!AUTO} || ${!AUTO} =~ "6" ]] && IPV6=$(ip -6 -br addr show scope global primary -deprecated dev $NETWORK | awk -v RS='[[:space:]]+' '(NR>2){print}' | grep -Pvm1 '^.+/128|^$') || IPV6=
       if [[ -n $IPV6 ]]; then
-        # get IPV6 subnet, preset to /64 if single host address is given
-        [[ ${IPV6#*/} == 128 ]] && SUBNET6=$(echo $IPV6 | sed -r 's/^([^:]+):([^:]+):([^:]+):([^:]+).*$/\1:\2:\3:\4::\/64/') || SUBNET6=$(ip -6 route show $IPV6 dev $NETWORK | awk '{print $1;exit}')
+        SUBNET6=$(ip -6 route show $IPV6 dev $NETWORK | awk '{print $1;exit}')
         SERVER6=${IPV6%/*}
         GATEWAY6=$(ip -6 route show default dev $NETWORK | awk '{print $3;exit}')
         # replace link local address for first address in subnet