rtnetlink: Clean up rtnl_setlink().

We will push RTNL down to rtnl_setlink().

Let's unify the error path to make it easy to place rtnl_net_lock().

While at it, keep the variables in reverse xmas order.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index a19b2eb2727e405a8e6d8955f88e045e159bc21f..f89a902458d6faf1228eb549de28816c64d2d8a2 100644 (file)
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3279,11 +3279,11 @@ static struct net_device *rtnl_dev_get(struct net *net,
 static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
                        struct netlink_ext_ack *extack)
 {
+       struct ifinfomsg *ifm = nlmsg_data(nlh);
        struct net *net = sock_net(skb->sk);
-       struct ifinfomsg *ifm;
-       struct net_device *dev;
-       int err;
        struct nlattr *tb[IFLA_MAX+1];
+       struct net_device *dev = NULL;
+       int err;
 
        err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFLA_MAX,
                                     ifla_policy, extack);
@@ -3294,21 +3294,18 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh,
        if (err < 0)
                goto errout;
 
-       err = -EINVAL;
-       ifm = nlmsg_data(nlh);
        if (ifm->ifi_index > 0)
                dev = __dev_get_by_index(net, ifm->ifi_index);
        else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME])
                dev = rtnl_dev_get(net, tb);
        else
-               goto errout;
+               err = -EINVAL;
 
-       if (dev == NULL) {
+       if (dev)
+               err = do_setlink(skb, dev, ifm, extack, tb, 0);
+       else if (!err)
                err = -ENODEV;
-               goto errout;
-       }
 
-       err = do_setlink(skb, dev, ifm, extack, tb, 0);
 errout:
        return err;
 }