diff -aur systemd-228-1/src/network/networkd-link.c systemd-228-1a/src/network/networkd-link.c --- systemd-228-1/src/network/networkd-link.c 2016-05-18 16:19:06.757698227 -0700 +++ systemd-228-1a/src/network/networkd-link.c 2016-05-18 16:25:20.219453171 -0700 @@ -134,6 +134,26 @@ return link->network->ip_forward & ADDRESS_FAMILY_IPV6; } +static bool link_ipv6_disabled(Link *link) { + const char *p = NULL; + int r; + if (link->flags & IFF_LOOPBACK) + return true; + /* Make this a NOP if IPv6 is not available */ + if (!socket_ipv6_is_supported()) + return true; + + p = strjoina("/proc/sys/net/ipv6/conf/", link->ifname, "/disable_ipv6"); + _cleanup_free_ char *val = NULL; + r = read_one_line_file(p, &val); + if (r < 0) + log_link_warning_errno(link, r, "Cannot read ipv6 state for interface: %m"); + if (streq(val, "0")) + return false; + + return true; +} + bool link_ipv6_accept_ra_enabled(Link *link) { if (link->flags & IFF_LOOPBACK) return false; @@ -614,7 +634,7 @@ !link->ipv4ll_route) return; - if (link_ipv6ll_enabled(link)) + if (!link_ipv6_disabled(link) && link_ipv6ll_enabled(link)) if (in_addr_is_null(AF_INET6, (const union in_addr_union*) &link->ipv6ll_address) > 0) return;