2 files changed, 17 insertions, 0 deletions

diff --git a/include/net/inet_sock.h b/include/net/inet_sock.h
index 625bdf95d673..012b1f91f3ec 100644
--- a/include/net/inet_sock.h
+++ b/include/net/inet_sock.h
@@ -28,6 +28,7 @@
 #include <net/request_sock.h>
 #include <net/netns/hash.h>
 #include <net/tcp_states.h>
+#include <net/l3mdev.h>
 
 /** struct ip_options - IP Options
  *
@@ -113,6 +114,19 @@ static inline u32 inet_request_mark(const struct sock *sk, struct sk_buff *skb)
         return sk->sk_mark;
 }
 
+static inline int inet_request_bound_dev_if(const struct sock *sk,
+                                            struct sk_buff *skb)
+{
+#ifdef CONFIG_NET_L3_MASTER_DEV
+        struct net *net = sock_net(sk);
+
+        if (!sk->sk_bound_dev_if && net->ipv4.sysctl_tcp_l3mdev_accept)
+                return l3mdev_master_ifindex_by_index(net, skb->skb_iif);
+#endif
+
+        return sk->sk_bound_dev_if;
+}
+
 struct inet_cork {
         unsigned int            flags;
         __be32                  addr;
diff --git a/include/net/netns/ipv4.h b/include/net/netns/ipv4.h
index c68926b4899c..d75be32650ba 100644
--- a/include/net/netns/ipv4.h
+++ b/include/net/netns/ipv4.h
@@ -86,6 +86,9 @@ struct netns_ipv4 {
 
         int sysctl_fwmark_reflect;
         int sysctl_tcp_fwmark_accept;
+#ifdef CONFIG_NET_L3_MASTER_DEV
+        int sysctl_tcp_l3mdev_accept;
+#endif
         int sysctl_tcp_mtu_probing;
         int sysctl_tcp_base_mss;
         int sysctl_tcp_probe_threshold;