[PATCH net-next] net/ipv4: Add extack message that dev is required for ONLINK

[dsahern]

From: David Ahern <dsah...@gmail.com>

Make IPv4 consistent with IPv6 and return an extack message that the
ONLINK flag requires a nexthop device.

Signed-off-by: David Ahern <dsah...@gmail.com>
---
 net/ipv4/fib_semantics.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index f3c89ccf14c5..bee8db979195 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -797,8 +797,10 @@ static int fib_check_nh(struct fib_config *cfg, struct 
fib_nh *nh,
                                return -EINVAL;
                        }
                        dev = __dev_get_by_index(net, nh->nh_oif);
-                       if (!dev)
+                       if (!dev) {
+                               NL_SET_ERR_MSG(extack, "Nexthop device required 
for onlink");
                                return -ENODEV;
+                       }
                        if (!(dev->flags & IFF_UP)) {
                                NL_SET_ERR_MSG(extack,
                                               "Nexthop device is not up");
-- 
2.11.0