lwtunnel: valid encap attr check should return 0 when lwtunnel is disabled
An error was reported upgrading to 4.9.8:
root@Typhoon:~# ip route add default table 210 nexthop dev eth0 via 10.68.64.1
weight 1 nexthop dev eth0 via 10.68.64.2 weight 1
RTNETLINK answers: Operation not supported
The problem occurs when CONFIG_LWTUNNEL is not enabled and a multipath
route is submitted.
The point of lwtunnel_valid_encap_type_attr is catch modules that
need to be loaded before any references are taken with rntl held. With
CONFIG_LWTUNNEL disabled, there will be no modules to load so the
lwtunnel_valid_encap_type_attr stub should just return 0.
Fixes: 9ed59592e3e3 ("lwtunnel: fix autoload of lwt modules")
Reported-by: pupilla@libero.it
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h
index 73dd876..0388b9c 100644
--- a/include/net/lwtunnel.h
+++ b/include/net/lwtunnel.h
@@ -178,7 +178,10 @@ static inline int lwtunnel_valid_encap_type(u16 encap_type)
}
static inline int lwtunnel_valid_encap_type_attr(struct nlattr *attr, int len)
{
- return -EOPNOTSUPP;
+ /* return 0 since we are not walking attr looking for
+ * RTA_ENCAP_TYPE attribute on nexthops.
+ */
+ return 0;
}
static inline int lwtunnel_build_state(struct net_device *dev, u16 encap_type,
