net: mpls: Pull common label check into helper

commit b7b386f42f079b25b942c756820e36c6bd09b2ca upstream.

mpls_route_add and mpls_route_del have the same checks on the label.
Move to a helper. Avoid duplicate extack messages in the next patch.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index c5a5a69..3e8d1f6 100644 (file)
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -756,6 +756,19 @@ errout:
        return err;
 }
 
+static bool mpls_label_ok(struct net *net, unsigned int index)
+{
+       /* Reserved labels may not be set */
+       if (index < MPLS_LABEL_FIRST_UNRESERVED)
+               return false;
+
+       /* The full 20 bit range may not be supported. */
+       if (index >= net->mpls.platform_labels)
+               return false;
+
+       return true;
+}
+
 static int mpls_route_add(struct mpls_route_config *cfg)
 {
        struct mpls_route __rcu **platform_label;
@@ -774,12 +787,7 @@ static int mpls_route_add(struct mpls_route_config *cfg)
                index = find_free_label(net);
        }
 
-       /* Reserved labels may not be set */
-       if (index < MPLS_LABEL_FIRST_UNRESERVED)
-               goto errout;
-
-       /* The full 20 bit range may not be supported. */
-       if (index >= net->mpls.platform_labels)
+       if (!mpls_label_ok(net, index))
                goto errout;
 
        /* Append makes no sense with mpls */
@@ -840,12 +848,7 @@ static int mpls_route_del(struct mpls_route_config *cfg)
 
        index = cfg->rc_label;
 
-       /* Reserved labels may not be removed */
-       if (index < MPLS_LABEL_FIRST_UNRESERVED)
-               goto errout;
-
-       /* The full 20 bit range may not be supported */
-       if (index >= net->mpls.platform_labels)
+       if (!mpls_label_ok(net, index))
                goto errout;
 
        mpls_route_update(net, index, NULL, &cfg->rc_nlinfo);
@@ -1279,10 +1282,9 @@ static int rtm_to_route_config(struct sk_buff *skb,  struct nlmsghdr *nlh,
                                           &cfg->rc_label))
                                goto errout;
 
-                       /* Reserved labels may not be set */
-                       if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED)
+                       if (!mpls_label_ok(cfg->rc_nlinfo.nl_net,
+                                          cfg->rc_label))
                                goto errout;
-
                        break;
                }
                case RTA_VIA: