addrconf: refuse isatap eui64 for INADDR_ANY

A tunnel with no local ipv4 endpoint would otherwise use the
ISATAP linklocal address fe80::5efe:0:0, which is invalid. Rather not
add a linklocal address at all.

Signed-off-by: Sascha Hlusiak <contact@saschahlusiak.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 9eb61c7cae57..31938e5fb220 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -1520,6 +1520,8 @@ static int addrconf_ifid_infiniband(u8 *eui, struct net_device *dev)
 
 int __ipv6_isatap_ifid(u8 *eui, __be32 addr)
 {
+        if (addr == 0)
+                return -1;
         eui[0] = (ipv4_is_zeronet(addr) || ipv4_is_private_10(addr) ||
                   ipv4_is_loopback(addr) || ipv4_is_linklocal_169(addr) ||
                   ipv4_is_private_172(addr) || ipv4_is_test_192(addr) ||