net: gre: provide multicast mappings for ipv4 and ipv6
My commit 6d55cb91a0020ac0 (gre: fix hard header destination
address checking) broke multicast.
The reason is that ip_gre used to get ipgre_header() calls with
zero destination if we have NOARP or multicast destination. Instead
the actual target was decided at ipgre_tunnel_xmit() time based on
per-protocol dissection.
Instead of allowing the "abuse" of ->header() calls with invalid
destination, this creates multicast mappings for ip_gre. This also
fixes "ip neigh show nud noarp" to display the proper multicast
mappings used by the gre device.
Reported-by: Doug Kehn <rdkehn@yahoo.com>
Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Acked-by: Doug Kehn <rdkehn@yahoo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c
index 090d273..1b74d3b 100644
--- a/net/ipv4/arp.c
+++ b/net/ipv4/arp.c
@@ -215,6 +215,9 @@
case ARPHRD_INFINIBAND:
ip_ib_mc_map(addr, dev->broadcast, haddr);
return 0;
+ case ARPHRD_IPGRE:
+ ip_ipgre_mc_map(addr, dev->broadcast, haddr);
+ return 0;
default:
if (dir) {
memcpy(haddr, dev->broadcast, dev->addr_len);