1 files changed, 35 insertions, 0 deletions

diff --git a/net/l3mdev/l3mdev.c b/net/l3mdev/l3mdev.c
index c4a1c3e84e12..43610e5acc4e 100644
--- a/net/l3mdev/l3mdev.c
+++ b/net/l3mdev/l3mdev.c
@@ -222,3 +222,38 @@ out:
 
         return rc;
 }
+
+void l3mdev_update_flow(struct net *net, struct flowi *fl)
+{
+        struct net_device *dev;
+        int ifindex;
+
+        rcu_read_lock();
+
+        if (fl->flowi_oif) {
+                dev = dev_get_by_index_rcu(net, fl->flowi_oif);
+                if (dev) {
+                        ifindex = l3mdev_master_ifindex_rcu(dev);
+                        if (ifindex) {
+                                fl->flowi_oif = ifindex;
+                                fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
+                                goto out;
+                        }
+                }
+        }
+
+        if (fl->flowi_iif) {
+                dev = dev_get_by_index_rcu(net, fl->flowi_iif);
+                if (dev) {
+                        ifindex = l3mdev_master_ifindex_rcu(dev);
+                        if (ifindex) {
+                                fl->flowi_iif = ifindex;
+                                fl->flowi_flags |= FLOWI_FLAG_SKIP_NH_OIF;
+                        }
+                }
+        }
+
+out:
+        rcu_read_unlock();
+}
+EXPORT_SYMBOL_GPL(l3mdev_update_flow);