1 files changed, 55 insertions, 33 deletions

diff --git a/net/bridge/br_vlan_tunnel.c b/net/bridge/br_vlan_tunnel.c
index 6d2c4eed2dc8..a966a6ec8263 100644
--- a/net/bridge/br_vlan_tunnel.c
+++ b/net/bridge/br_vlan_tunnel.c
@@ -1,13 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  *	Bridge per vlan tunnel port dst_metadata handling code
  *
  *	Authors:
  *	Roopa Prabhu		<roopa@cumulusnetworks.com>
- *
- *	This program is free software; you can redistribute it and/or
- *	modify it under the terms of the GNU General Public License
- *	as published by the Free Software Foundation; either version
- *	2 of the License, or (at your option) any later version.
  */
 
 #include <linux/kernel.h>
@@ -34,48 +30,55 @@ static const struct rhashtable_params br_vlan_tunnel_rht_params = {
 	.key_offset = offsetof(struct net_bridge_vlan, tinfo.tunnel_id),
 	.key_len = sizeof(__be64),
 	.nelem_hint = 3,
-	.locks_mul = 1,
 	.obj_cmpfn = br_vlan_tunid_cmp,
 	.automatic_shrinking = true,
 };
 
 static struct net_bridge_vlan *br_vlan_tunnel_lookup(struct rhashtable *tbl,
-						     u64 tunnel_id)
+						     __be64 tunnel_id)
 {
 	return rhashtable_lookup_fast(tbl, &tunnel_id,
 				      br_vlan_tunnel_rht_params);
 }
 
+static void vlan_tunnel_info_release(struct net_bridge_vlan *vlan)
+{
+	struct metadata_dst *tdst = rtnl_dereference(vlan->tinfo.tunnel_dst);
+
+	WRITE_ONCE(vlan->tinfo.tunnel_id, 0);
+	RCU_INIT_POINTER(vlan->tinfo.tunnel_dst, NULL);
+	dst_release(&tdst->dst);
+}
+
 void vlan_tunnel_info_del(struct net_bridge_vlan_group *vg,
 			  struct net_bridge_vlan *vlan)
 {
-	if (!vlan->tinfo.tunnel_dst)
+	if (!rcu_access_pointer(vlan->tinfo.tunnel_dst))
 		return;
 	rhashtable_remove_fast(&vg->tunnel_hash, &vlan->tnode,
 			       br_vlan_tunnel_rht_params);
-	vlan->tinfo.tunnel_id = 0;
-	dst_release(&vlan->tinfo.tunnel_dst->dst);
-	vlan->tinfo.tunnel_dst = NULL;
+	vlan_tunnel_info_release(vlan);
 }
 
 static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
 				  struct net_bridge_vlan *vlan, u32 tun_id)
 {
-	struct metadata_dst *metadata = NULL;
+	struct metadata_dst *metadata = rtnl_dereference(vlan->tinfo.tunnel_dst);
 	__be64 key = key32_to_tunnel_id(cpu_to_be32(tun_id));
+	IP_TUNNEL_DECLARE_FLAGS(flags) = { };
 	int err;
 
-	if (vlan->tinfo.tunnel_dst)
+	if (metadata)
 		return -EEXIST;
 
-	metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, TUNNEL_KEY,
-				    key, 0);
+	__set_bit(IP_TUNNEL_KEY_BIT, flags);
+	metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, flags, key, 0);
 	if (!metadata)
 		return -EINVAL;
 
 	metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_BRIDGE;
-	vlan->tinfo.tunnel_dst = metadata;
-	vlan->tinfo.tunnel_id = key;
+	rcu_assign_pointer(vlan->tinfo.tunnel_dst, metadata);
+	WRITE_ONCE(vlan->tinfo.tunnel_id, key);
 
 	err = rhashtable_lookup_insert_fast(&vg->tunnel_hash, &vlan->tnode,
 					    br_vlan_tunnel_rht_params);
@@ -84,9 +87,7 @@ static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
 
 	return 0;
 out:
-	dst_release(&vlan->tinfo.tunnel_dst->dst);
-	vlan->tinfo.tunnel_dst = NULL;
-	vlan->tinfo.tunnel_id = 0;
+	vlan_tunnel_info_release(vlan);
 
 	return err;
 }
@@ -94,7 +95,8 @@ out:
 /* Must be protected by RTNL.
  * Must be called with vid in range from 1 to 4094 inclusive.
  */
-int nbp_vlan_tunnel_info_add(struct net_bridge_port *port, u16 vid, u32 tun_id)
+int nbp_vlan_tunnel_info_add(const struct net_bridge_port *port, u16 vid,
+			     u32 tun_id)
 {
 	struct net_bridge_vlan_group *vg;
 	struct net_bridge_vlan *vlan;
@@ -112,7 +114,7 @@ int nbp_vlan_tunnel_info_add(struct net_bridge_port *port, u16 vid, u32 tun_id)
 /* Must be protected by RTNL.
  * Must be called with vid in range from 1 to 4094 inclusive.
  */
-int nbp_vlan_tunnel_info_delete(struct net_bridge_port *port, u16 vid)
+int nbp_vlan_tunnel_info_delete(const struct net_bridge_port *port, u16 vid)
 {
 	struct net_bridge_vlan_group *vg;
 	struct net_bridge_vlan *v;
@@ -157,41 +159,43 @@ void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
 	rhashtable_destroy(&vg->tunnel_hash);
 }
 
-int br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
-				  struct net_bridge_port *p,
-				  struct net_bridge_vlan_group *vg)
+void br_handle_ingress_vlan_tunnel(struct sk_buff *skb,
+				   struct net_bridge_port *p,
+				   struct net_bridge_vlan_group *vg)
 {
 	struct ip_tunnel_info *tinfo = skb_tunnel_info(skb);
 	struct net_bridge_vlan *vlan;
 
 	if (!vg || !tinfo)
-		return 0;
+		return;
 
 	/* if already tagged, ignore */
 	if (skb_vlan_tagged(skb))
-		return 0;
+		return;
 
 	/* lookup vid, given tunnel id */
 	vlan = br_vlan_tunnel_lookup(&vg->tunnel_hash, tinfo->key.tun_id);
 	if (!vlan)
-		return 0;
+		return;
 
 	skb_dst_drop(skb);
 
 	__vlan_hwaccel_put_tag(skb, p->br->vlan_proto, vlan->vid);
-
-	return 0;
 }
 
 int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
 				 struct net_bridge_vlan *vlan)
 {
+	IP_TUNNEL_DECLARE_FLAGS(flags) = { };
+	struct metadata_dst *tunnel_dst;
+	__be64 tunnel_id;
 	int err;
 
-	if (!vlan || !vlan->tinfo.tunnel_id)
+	if (!vlan)
 		return 0;
 
-	if (unlikely(!skb_vlan_tag_present(skb)))
+	tunnel_id = READ_ONCE(vlan->tinfo.tunnel_id);
+	if (!tunnel_id || unlikely(!skb_vlan_tag_present(skb)))
 		return 0;
 
 	skb_dst_drop(skb);
@@ -199,7 +203,25 @@ int br_handle_egress_vlan_tunnel(struct sk_buff *skb,
 	if (err)
 		return err;
 
-	skb_dst_set(skb, dst_clone(&vlan->tinfo.tunnel_dst->dst));
+	if (BR_INPUT_SKB_CB(skb)->backup_nhid) {
+		__set_bit(IP_TUNNEL_KEY_BIT, flags);
+		tunnel_dst = __ip_tun_set_dst(0, 0, 0, 0, 0, flags,
+					      tunnel_id, 0);
+		if (!tunnel_dst)
+			return -ENOMEM;
+
+		tunnel_dst->u.tun_info.mode |= IP_TUNNEL_INFO_TX |
+					       IP_TUNNEL_INFO_BRIDGE;
+		tunnel_dst->u.tun_info.key.nhid =
+			BR_INPUT_SKB_CB(skb)->backup_nhid;
+		skb_dst_set(skb, &tunnel_dst->dst);
+
+		return 0;
+	}
+
+	tunnel_dst = rcu_dereference(vlan->tinfo.tunnel_dst);
+	if (tunnel_dst && dst_hold_safe(&tunnel_dst->dst))
+		skb_dst_set(skb, &tunnel_dst->dst);
 
 	return 0;
 }