[NETNS][IPV6]: inet6_addr - check ipv6 address per namespace

When a new address is added, we must check if the new address does not
already exists.  This patch makes this check to be aware of a network
namespace, so the check will look if the address already exists for
the specified network namespace. While the addresses are browsed, the
addresses which do not belong to the namespace are discarded.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: Benjamin Thery <benjamin.thery@bull.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/addrconf.h b/include/net/addrconf.h
index 1c3a560..d1697b5 100644
--- a/include/net/addrconf.h
+++ b/include/net/addrconf.h
@@ -59,9 +59,11 @@
 extern int			addrconf_del_ifaddr(void __user *arg);
 extern int			addrconf_set_dstaddr(void __user *arg);
 
-extern int			ipv6_chk_addr(struct in6_addr *addr,
+extern int			ipv6_chk_addr(struct net *net,
+					      struct in6_addr *addr,
 					      struct net_device *dev,
 					      int strict);
+
 #if defined(CONFIG_IPV6_MIP6) || defined(CONFIG_IPV6_MIP6_MODULE)
 extern int			ipv6_chk_home_addr(struct in6_addr *addr);
 #endif