af_mpls: fix undefined reference to ip6_route_output

Undefined reference to ip6_route_output and ip_route_output
was reported with CONFIG_INET=n and CONFIG_IPV6=n.

This patch uses ipv6_stub_impl.ipv6_dst_lookup instead of
ip6_route_output. And wraps affected code under
IS_ENABLED(CONFIG_INET) and IS_ENABLED(CONFIG_IPV6).

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Reported-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c
index 49f1b0e..88cfaa2 100644 (file)
--- a/net/mpls/af_mpls.c
+++ b/net/mpls/af_mpls.c
@@ -15,7 +15,10 @@
 #include <net/ip_fib.h>
 #include <net/netevent.h>
 #include <net/netns/generic.h>
-#include <net/ip6_route.h>
+#if IS_ENABLED(CONFIG_IPV6)
+#include <net/ipv6.h>
+#include <net/addrconf.h>
+#endif
 #include "internal.h"
 
 #define LABEL_NOT_SPECIFIED (1<<20)
@@ -331,6 +334,7 @@ static unsigned find_free_label(struct net *net)
        return LABEL_NOT_SPECIFIED;
 }
 
+#if IS_ENABLED(CONFIG_INET)
 static struct net_device *inet_fib_lookup_dev(struct net *net, void *addr)
 {
        struct net_device *dev = NULL;
@@ -347,30 +351,49 @@ static struct net_device *inet_fib_lookup_dev(struct net *net, void *addr)
 
        ip_rt_put(rt);
 
-errout:
        return dev;
+errout:
+       return ERR_PTR(-ENODEV);
+}
+#else
+static struct net_device *inet_fib_lookup_dev(struct net *net, void *addr)
+{
+       return ERR_PTR(-EAFNOSUPPORT);
 }
+#endif
 
+#if IS_ENABLED(CONFIG_IPV6)
 static struct net_device *inet6_fib_lookup_dev(struct net *net, void *addr)
 {
        struct net_device *dev = NULL;
        struct dst_entry *dst;
        struct flowi6 fl6;
+       int err;
+
+       if (!ipv6_stub)
+               return ERR_PTR(-EAFNOSUPPORT);
 
        memset(&fl6, 0, sizeof(fl6));
        memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
-       dst = ip6_route_output(net, NULL, &fl6);
-       if (dst->error)
+       err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
+       if (err)
                goto errout;
 
        dev = dst->dev;
        dev_hold(dev);
-
-errout:
        dst_release(dst);
 
        return dev;
+
+errout:
+       return ERR_PTR(err);
 }
+#else
+static struct net_device *inet6_fib_lookup_dev(struct net *net, void *addr)
+{
+       return ERR_PTR(-EAFNOSUPPORT);
+}
+#endif
 
 static struct net_device *find_outdev(struct net *net,
                                      struct mpls_route_config *cfg)
@@ -425,10 +448,12 @@ static int mpls_route_add(struct mpls_route_config *cfg)
        if (cfg->rc_output_labels > MAX_NEW_LABELS)
                goto errout;
 
-       err = -ENODEV;
        dev = find_outdev(net, cfg);
-       if (!dev)
+       if (IS_ERR(dev)) {
+               err = PTR_ERR(dev);
+               dev = NULL;
                goto errout;
+       }
 
        /* Ensure this is a supported device */
        err = -EINVAL;