1 files changed, 60 insertions, 2 deletions

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 1653e3377cb3..12998bf04e55 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -7,6 +7,7 @@
 #ifndef __DSA_PRIV_H
 #define __DSA_PRIV_H
 
+#include <linux/if_bridge.h>
 #include <linux/phy.h>
 #include <linux/netdevice.h>
 #include <linux/netpoll.h>
@@ -164,8 +165,6 @@ int dsa_port_vlan_add(struct dsa_port *dp,
 		      struct switchdev_trans *trans);
 int dsa_port_vlan_del(struct dsa_port *dp,
 		      const struct switchdev_obj_port_vlan *vlan);
-int dsa_port_vid_add(struct dsa_port *dp, u16 vid, u16 flags);
-int dsa_port_vid_del(struct dsa_port *dp, u16 vid);
 int dsa_port_link_register_of(struct dsa_port *dp);
 void dsa_port_link_unregister_of(struct dsa_port *dp);
 extern const struct phylink_mac_ops dsa_port_phylink_mac_ops;
@@ -196,6 +195,65 @@ dsa_slave_to_master(const struct net_device *dev)
 	return dp->cpu_dp->master;
 }
 
+/* If under a bridge with vlan_filtering=0, make sure to send pvid-tagged
+ * frames as untagged, since the bridge will not untag them.
+ */
+static inline struct sk_buff *dsa_untag_bridge_pvid(struct sk_buff *skb)
+{
+	struct dsa_port *dp = dsa_slave_to_port(skb->dev);
+	struct net_device *br = dp->bridge_dev;
+	struct net_device *dev = skb->dev;
+	struct net_device *upper_dev;
+	u16 vid, pvid, proto;
+	int err;
+
+	if (!br || br_vlan_enabled(br))
+		return skb;
+
+	err = br_vlan_get_proto(br, &proto);
+	if (err)
+		return skb;
+
+	/* Move VLAN tag from data to hwaccel */
+	if (!skb_vlan_tag_present(skb) && skb->protocol == htons(proto)) {
+		skb = skb_vlan_untag(skb);
+		if (!skb)
+			return NULL;
+	}
+
+	if (!skb_vlan_tag_present(skb))
+		return skb;
+
+	vid = skb_vlan_tag_get_id(skb);
+
+	/* We already run under an RCU read-side critical section since
+	 * we are called from netif_receive_skb_list_internal().
+	 */
+	err = br_vlan_get_pvid_rcu(dev, &pvid);
+	if (err)
+		return skb;
+
+	if (vid != pvid)
+		return skb;
+
+	/* The sad part about attempting to untag from DSA is that we
+	 * don't know, unless we check, if the skb will end up in
+	 * the bridge's data path - br_allowed_ingress() - or not.
+	 * For example, there might be an 8021q upper for the
+	 * default_pvid of the bridge, which will steal VLAN-tagged traffic
+	 * from the bridge's data path. This is a configuration that DSA
+	 * supports because vlan_filtering is 0. In that case, we should
+	 * definitely keep the tag, to make sure it keeps working.
+	 */
+	upper_dev = __vlan_find_dev_deep_rcu(br, htons(proto), vid);
+	if (upper_dev)
+		return skb;
+
+	__vlan_hwaccel_clear_tag(skb);
+
+	return skb;
+}
+
 /* switch.c */
 int dsa_switch_register_notifier(struct dsa_switch *ds);
 void dsa_switch_unregister_notifier(struct dsa_switch *ds);