From c88fd204e9822cd92d97a93f9120c9d58d3a5037 Mon Sep 17 00:00:00 2001
From: Tom Gundersen <teg@jklm.no>
Date: Mon, 25 May 2015 17:34:47 +0200
Subject: [PATCH] networkd: fix IFF_UP when ipv6 support is disabled

Passing ipv6 options (even when they should be noops) caused IFF_UP to fail when
ipv6 was supported.

Fixes: https://bugs.freedesktop.org/show_bug.cgi?id=90103
(cherry picked from commit 01d28f81a782616b6daa84a42447fd4939783a66)
---
 src/network/networkd-link.c | 31 +++++++++++++++++--------------
 1 file changed, 17 insertions(+), 14 deletions(-)

diff --git a/src/network/networkd-link.c b/src/network/networkd-link.c
index 8b0de1f741..f039a2d687 100644
--- a/src/network/networkd-link.c
+++ b/src/network/networkd-link.c
@@ -1010,27 +1010,30 @@ static int link_up(Link *link) {
         if (r < 0)
                 return log_link_error_errno(link, r, "Could not open IFLA_AF_SPEC container: %m");
 
-        r = sd_rtnl_message_open_container(req, AF_INET6);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not open AF_INET6 container: %m");
+        if (socket_ipv6_is_supported()) {
+                /* if the kernel lacks ipv6 support setting IFF_UP fails if any ipv6 options are passed */
+                r = sd_rtnl_message_open_container(req, AF_INET6);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "Could not open AF_INET6 container: %m");
 
-        ipv6ll_mode = link_ipv6ll_enabled(link) ? IN6_ADDR_GEN_MODE_EUI64 : IN6_ADDR_GEN_MODE_NONE;
-        r = sd_rtnl_message_append_u8(req, IFLA_INET6_ADDR_GEN_MODE, ipv6ll_mode);
-        if (r < 0)
-                return log_link_error_errno(link, r, "Could not append IFLA_INET6_ADDR_GEN_MODE: %m");
+                ipv6ll_mode = link_ipv6ll_enabled(link) ? IN6_ADDR_GEN_MODE_EUI64 : IN6_ADDR_GEN_MODE_NONE;
+                r = sd_rtnl_message_append_u8(req, IFLA_INET6_ADDR_GEN_MODE, ipv6ll_mode);
+                if (r < 0)
+                        return log_link_error_errno(link, r, "Could not append IFLA_INET6_ADDR_GEN_MODE: %m");
+
+                if (!in_addr_is_null(AF_INET6, &link->network->ipv6_token)) {
+                        r = sd_rtnl_message_append_in6_addr(req, IFLA_INET6_TOKEN, &link->network->ipv6_token.in6);
+                        if (r < 0)
+                                return log_link_error_errno(link, r, "Could not append IFLA_INET6_TOKEN: %m");
+                }
 
-        if (!in_addr_is_null(AF_INET6, &link->network->ipv6_token)) {
-                r = sd_rtnl_message_append_in6_addr(req, IFLA_INET6_TOKEN, &link->network->ipv6_token.in6);
+                r = sd_rtnl_message_close_container(req);
                 if (r < 0)
-                        return log_link_error_errno(link, r, "Could not append IFLA_INET6_TOKEN: %m");
+                        return log_link_error_errno(link, r, "Could not close AF_INET6 container: %m");
         }
 
         r = sd_rtnl_message_close_container(req);
         if (r < 0)
-                return log_link_error_errno(link, r, "Could not close AF_INET6 container: %m");
-
-        r = sd_rtnl_message_close_container(req);
-        if (r < 0)
                 return log_link_error_errno(link, r, "Could not close IFLA_AF_SPEC container: %m");
 
         r = sd_rtnl_call_async(link->manager->rtnl, req, link_up_handler, link, 0, NULL);