3 files changed, 33 insertions, 5 deletions
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index 7e9a789be5e0..ca1ad9ebbc92 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -123,12 +123,12 @@ struct inet6_skb_parm {
 };
 
 #if defined(CONFIG_NET_L3_MASTER_DEV)
-static inline bool skb_l3mdev_slave(__u16 flags)
+static inline bool ipv6_l3mdev_skb(__u16 flags)
 {
 	return flags & IP6SKB_L3SLAVE;
 }
 #else
-static inline bool skb_l3mdev_slave(__u16 flags)
+static inline bool ipv6_l3mdev_skb(__u16 flags)
 {
 	return false;
 }
@@ -139,11 +139,22 @@ static inline bool skb_l3mdev_slave(__u16 flags)
 
 static inline int inet6_iif(const struct sk_buff *skb)
 {
-	bool l3_slave = skb_l3mdev_slave(IP6CB(skb)->flags);
+	bool l3_slave = ipv6_l3mdev_skb(IP6CB(skb)->flags);
 
 	return l3_slave ? skb->skb_iif : IP6CB(skb)->iif;
 }
 
+/* can not be used in TCP layer after tcp_v6_fill_cb */
+static inline bool inet6_exact_dif_match(struct net *net, struct sk_buff *skb)
+{
+#if defined(CONFIG_NET_L3_MASTER_DEV)
+	if (!net->ipv4.sysctl_tcp_l3mdev_accept &&
+	    ipv6_l3mdev_skb(IP6CB(skb)->flags))
+		return true;
+#endif
+	return false;
+}
+
 struct tcp6_request_sock {
 	struct tcp_request_sock	  tcp6rsk_tcp;
 };
diff --git a/include/net/ip.h b/include/net/ip.h
index bc43c0fcae12..c9d07988911e 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -38,7 +38,7 @@ struct sock;
 struct inet_skb_parm {
 	int			iif;
 	struct ip_options	opt;		/* Compiled IP options		*/
-	unsigned char		flags;
+	u16			flags;
 
 #define IPSKB_FORWARDED		BIT(0)
 #define IPSKB_XFRM_TUNNEL_SIZE	BIT(1)
@@ -48,10 +48,16 @@ struct inet_skb_parm {
 #define IPSKB_DOREDIRECT	BIT(5)
 #define IPSKB_FRAG_PMTU		BIT(6)
 #define IPSKB_FRAG_SEGS		BIT(7)
+#define IPSKB_L3SLAVE		BIT(8)
 
 	u16			frag_max_size;
 };
 
+static inline bool ipv4_l3mdev_skb(u16 flags)
+{
+	return !!(flags & IPSKB_L3SLAVE);
+}
+
 static inline unsigned int ip_hdrlen(const struct sk_buff *skb)
 {
 	return ip_hdr(skb)->ihl * 4;
diff --git a/include/net/tcp.h b/include/net/tcp.h
index f83b7f220a65..5b82d4d94834 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -794,12 +794,23 @@ struct tcp_skb_cb {
  */
 static inline int tcp_v6_iif(const struct sk_buff *skb)
 {
-	bool l3_slave = skb_l3mdev_slave(TCP_SKB_CB(skb)->header.h6.flags);
+	bool l3_slave = ipv6_l3mdev_skb(TCP_SKB_CB(skb)->header.h6.flags);
 
 	return l3_slave ? skb->skb_iif : TCP_SKB_CB(skb)->header.h6.iif;
 }
 #endif
 
+/* TCP_SKB_CB reference means this can not be used from early demux */
+static inline bool inet_exact_dif_match(struct net *net, struct sk_buff *skb)
+{
+#if IS_ENABLED(CONFIG_NET_L3_MASTER_DEV)
+	if (!net->ipv4.sysctl_tcp_l3mdev_accept &&
+	    ipv4_l3mdev_skb(TCP_SKB_CB(skb)->header.h4.flags))
+		return true;
+#endif
+	return false;
+}
+
 /* Due to TSO, an SKB can be composed of multiple actual
  * packets.  To keep these tracked properly, we use this.
  */