From: Yu Watanabe <watanabe.yu+github@gmail.com>
Date: Mon, 1 Aug 2022 18:33:21 +0000 (+0900)
Subject: network: make link_may_have_ipv6ll() optionally check Multicast= setting
X-Git-Tag: v252-rc1~546^2~1
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=bd7e0a3f1cd28fd00d7c21bea766bffb42917c36;p=thirdparty%2Fsystemd.git

network: make link_may_have_ipv6ll() optionally check Multicast= setting

Fixes the IPv6LL issue in #23197.
---

diff --git a/src/network/networkd-address.c b/src/network/networkd-address.c
index a60cd746a4b..ccb4a426fae 100644
--- a/src/network/networkd-address.c
+++ b/src/network/networkd-address.c
@@ -802,7 +802,7 @@ int link_drop_ipv6ll_addresses(Link *link) {
         /* IPv6LL address may be in the tentative state, and in that case networkd has not received it.
          * So, we need to dump all IPv6 addresses. */
 
-        if (link_may_have_ipv6ll(link))
+        if (link_may_have_ipv6ll(link, /* check_multicast = */ false))
                 return 0;
 
         r = sd_rtnl_message_new_addr(link->manager->rtnl, &req, RTM_GETADDR, link->ifindex, AF_INET6);
diff --git a/src/network/networkd-ipv6ll.c b/src/network/networkd-ipv6ll.c
index 9b859897019..32229a3fc70 100644
--- a/src/network/networkd-ipv6ll.c
+++ b/src/network/networkd-ipv6ll.c
@@ -38,7 +38,7 @@ bool link_ipv6ll_enabled(Link *link) {
         return link->network->link_local & ADDRESS_FAMILY_IPV6;
 }
 
-bool link_may_have_ipv6ll(Link *link) {
+bool link_may_have_ipv6ll(Link *link, bool check_multicast) {
         assert(link);
 
         /*
@@ -62,6 +62,9 @@ bool link_may_have_ipv6ll(Link *link) {
                 if (!link->network)
                         return false;
 
+                if (check_multicast && !FLAGS_SET(link->flags, IFF_MULTICAST) && link->network->multicast <= 0)
+                        return false;
+
                 ORDERED_HASHMAP_FOREACH(a, link->network->addresses_by_section) {
                         if (a->family != AF_INET6)
                                 continue;
diff --git a/src/network/networkd-ipv6ll.h b/src/network/networkd-ipv6ll.h
index a9763debb1a..2759eed7f70 100644
--- a/src/network/networkd-ipv6ll.h
+++ b/src/network/networkd-ipv6ll.h
@@ -22,7 +22,7 @@ typedef enum IPv6LinkLocalAddressGenMode {
 } IPv6LinkLocalAddressGenMode;
 
 bool link_ipv6ll_enabled(Link *link);
-bool link_may_have_ipv6ll(Link *link);
+bool link_may_have_ipv6ll(Link *link, bool check_multicast);
 
 IPv6LinkLocalAddressGenMode link_get_ipv6ll_addrgen_mode(Link *link);
 int ipv6ll_addrgen_mode_fill_message(sd_netlink_message *message, IPv6LinkLocalAddressGenMode mode);
diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index c8df554cd62..76e0690aefc 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -83,8 +83,7 @@ bool link_ipv6_enabled(Link *link) {
         if (link->network->bond)
                 return false;
 
-        /* DHCPv6 client will not be started if no IPv6 link-local address is configured. */
-        if (link_ipv6ll_enabled(link))
+        if (link_may_have_ipv6ll(link, /* check_multicast = */ false))
                 return true;
 
         if (network_has_static_ipv6_configurations(link->network))
diff --git a/src/network/networkd-ndisc.c b/src/network/networkd-ndisc.c
index 943e12ba560..dfbb7043bf1 100644
--- a/src/network/networkd-ndisc.c
+++ b/src/network/networkd-ndisc.c
@@ -41,7 +41,7 @@ bool link_ipv6_accept_ra_enabled(Link *link) {
         if (!link->network)
                 return false;
 
-        if (!link_may_have_ipv6ll(link))
+        if (!link_may_have_ipv6ll(link, /* check_multicast = */ true))
                 return false;
 
         assert(link->network->ipv6_accept_ra >= 0);
diff --git a/src/network/networkd-radv.c b/src/network/networkd-radv.c
index 32ee7aa7abf..c59ae826940 100644
--- a/src/network/networkd-radv.c
+++ b/src/network/networkd-radv.c
@@ -54,7 +54,7 @@ void network_adjust_radv(Network *network) {
 bool link_radv_enabled(Link *link) {
         assert(link);
 
-        if (!link_may_have_ipv6ll(link))
+        if (!link_may_have_ipv6ll(link, /* check_multicast = */ true))
                 return false;
 
         if (link->hw_addr.length != ETH_ALEN)