1 files changed, 29 insertions, 12 deletions

diff --git a/net/core/dst.c b/net/core/dst.c
index 95f533844f17..e9d35f49c9e7 100644
--- a/net/core/dst.c
+++ b/net/core/dst.c
@@ -109,9 +109,6 @@ static void dst_destroy(struct dst_entry *dst)
 		child = xdst->child;
 	}
 #endif
-	if (!(dst->flags & DST_NOCOUNT))
-		dst_entries_add(dst->ops, -1);
-
 	if (dst->ops->destroy)
 		dst->ops->destroy(dst);
 	netdev_put(dst->dev, &dst->dev_tracker);
@@ -148,28 +145,46 @@ void dst_dev_put(struct dst_entry *dst)
 {
 	struct net_device *dev = dst->dev;
 
-	dst->obsolete = DST_OBSOLETE_DEAD;
+	WRITE_ONCE(dst->obsolete, DST_OBSOLETE_DEAD);
 	if (dst->ops->ifdown)
 		dst->ops->ifdown(dst, dev);
-	dst->input = dst_discard;
-	dst->output = dst_discard_out;
-	dst->dev = blackhole_netdev;
+	WRITE_ONCE(dst->input, dst_discard);
+	WRITE_ONCE(dst->output, dst_discard_out);
+	rcu_assign_pointer(dst->dev_rcu, blackhole_netdev);
 	netdev_ref_replace(dev, blackhole_netdev, &dst->dev_tracker,
 			   GFP_ATOMIC);
 }
 EXPORT_SYMBOL(dst_dev_put);
 
+static void dst_count_dec(struct dst_entry *dst)
+{
+	if (!(dst->flags & DST_NOCOUNT))
+		dst_entries_add(dst->ops, -1);
+}
+
 void dst_release(struct dst_entry *dst)
 {
-	if (dst && rcuref_put(&dst->__rcuref))
+	if (dst && rcuref_put(&dst->__rcuref)) {
+#ifdef CONFIG_DST_CACHE
+		if (dst->flags & DST_METADATA) {
+			struct metadata_dst *md_dst = (struct metadata_dst *)dst;
+
+			if (md_dst->type == METADATA_IP_TUNNEL)
+				dst_cache_reset_now(&md_dst->u.tun_info.dst_cache);
+		}
+#endif
+		dst_count_dec(dst);
 		call_rcu_hurry(&dst->rcu_head, dst_destroy_rcu);
+	}
 }
 EXPORT_SYMBOL(dst_release);
 
 void dst_release_immediate(struct dst_entry *dst)
 {
-	if (dst && rcuref_put(&dst->__rcuref))
+	if (dst && rcuref_put(&dst->__rcuref)) {
+		dst_count_dec(dst);
 		dst_destroy(dst);
+	}
 }
 EXPORT_SYMBOL(dst_release_immediate);
 
@@ -248,7 +263,7 @@ unsigned int dst_blackhole_mtu(const struct dst_entry *dst)
 {
 	unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
 
-	return mtu ? : dst->dev->mtu;
+	return mtu ? : dst_dev(dst)->mtu;
 }
 EXPORT_SYMBOL_GPL(dst_blackhole_mtu);
 
@@ -279,7 +294,8 @@ struct metadata_dst *metadata_dst_alloc(u8 optslen, enum metadata_type type,
 {
 	struct metadata_dst *md_dst;
 
-	md_dst = kmalloc(sizeof(*md_dst) + optslen, flags);
+	md_dst = kmalloc(struct_size(md_dst, u.tun_info.options, optslen),
+			 flags);
 	if (!md_dst)
 		return NULL;
 
@@ -307,7 +323,8 @@ metadata_dst_alloc_percpu(u8 optslen, enum metadata_type type, gfp_t flags)
 	int cpu;
 	struct metadata_dst __percpu *md_dst;
 
-	md_dst = __alloc_percpu_gfp(sizeof(struct metadata_dst) + optslen,
+	md_dst = __alloc_percpu_gfp(struct_size(md_dst, u.tun_info.options,
+						optslen),
 				    __alignof__(struct metadata_dst), flags);
 	if (!md_dst)
 		return NULL;