[RTNL]: Add missing link netlink attribute policy definitions

IFLA_LINK is no longer a write-only attribute on the kernel side and
must thus be validated. Same goes for the newly introduced
IFLA_LINKINFO.

Fixes undefined behaviour if either of the attributes are not well
formed.
Signed-off-by: NThomas Graf <tgraf@suug.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/core/rtnetlink.c

@@ -689,10 +689,12 @@ const struct nla_policy ifla_policy[IFLA_MAX+1] = {
 	[IFLA_BROADCAST]	= { .type = NLA_BINARY, .len = MAX_ADDR_LEN },
 	[IFLA_MAP]		= { .len = sizeof(struct rtnl_link_ifmap) },
 	[IFLA_MTU]		= { .type = NLA_U32 },
+	[IFLA_LINK]		= { .type = NLA_U32 },
 	[IFLA_TXQLEN]		= { .type = NLA_U32 },
 	[IFLA_WEIGHT]		= { .type = NLA_U32 },
 	[IFLA_OPERSTATE]	= { .type = NLA_U8 },
 	[IFLA_LINKMODE]		= { .type = NLA_U8 },
+	[IFLA_LINKINFO]		= { .type = NLA_NESTED },
 	[IFLA_NET_NS_PID]	= { .type = NLA_U32 },
 };