Update Linux to v5.4.148

Sourced from [1]

[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.4.148.tar.gz

Change-Id: Ib3d26c5ba9b022e2e03533005c4fed4d7c30b61b
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/net/hsr/hsr_debugfs.c b/net/hsr/hsr_debugfs.c
index 9444797..d5f709b 100644
--- a/net/hsr/hsr_debugfs.c
+++ b/net/hsr/hsr_debugfs.c
@@ -20,6 +20,8 @@
 #include "hsr_main.h"
 #include "hsr_framereg.h"
 
+static struct dentry *hsr_debugfs_root_dir;
+
 static void print_mac_address(struct seq_file *sfp, unsigned char *mac)
 {
 	seq_printf(sfp, "%02x:%02x:%02x:%02x:%02x:%02x:",
@@ -63,8 +65,20 @@
 	return single_open(filp, hsr_node_table_show, inode->i_private);
 }
 
+void hsr_debugfs_rename(struct net_device *dev)
+{
+	struct hsr_priv *priv = netdev_priv(dev);
+	struct dentry *d;
+
+	d = debugfs_rename(hsr_debugfs_root_dir, priv->node_tbl_root,
+			   hsr_debugfs_root_dir, dev->name);
+	if (IS_ERR(d))
+		netdev_warn(dev, "failed to rename\n");
+	else
+		priv->node_tbl_root = d;
+}
+
 static const struct file_operations hsr_fops = {
-	.owner	= THIS_MODULE,
 	.open	= hsr_node_table_open,
 	.read	= seq_read,
 	.llseek = seq_lseek,
@@ -78,15 +92,14 @@
  * When debugfs is configured this routine sets up the node_table file per
  * hsr device for dumping the node_table entries
  */
-int hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev)
+void hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev)
 {
-	int rc = -1;
 	struct dentry *de = NULL;
 
-	de = debugfs_create_dir(hsr_dev->name, NULL);
-	if (!de) {
-		pr_err("Cannot create hsr debugfs root\n");
-		return rc;
+	de = debugfs_create_dir(hsr_dev->name, hsr_debugfs_root_dir);
+	if (IS_ERR(de)) {
+		pr_err("Cannot create hsr debugfs directory\n");
+		return;
 	}
 
 	priv->node_tbl_root = de;
@@ -94,13 +107,13 @@
 	de = debugfs_create_file("node_table", S_IFREG | 0444,
 				 priv->node_tbl_root, priv,
 				 &hsr_fops);
-	if (!de) {
-		pr_err("Cannot create hsr node_table directory\n");
-		return rc;
+	if (IS_ERR(de)) {
+		pr_err("Cannot create hsr node_table file\n");
+		debugfs_remove(priv->node_tbl_root);
+		priv->node_tbl_root = NULL;
+		return;
 	}
 	priv->node_tbl_file = de;
-
-	return 0;
 }
 
 /* hsr_debugfs_term - Tear down debugfs intrastructure
@@ -117,3 +130,18 @@
 	debugfs_remove(priv->node_tbl_root);
 	priv->node_tbl_root = NULL;
 }
+
+void hsr_debugfs_create_root(void)
+{
+	hsr_debugfs_root_dir = debugfs_create_dir("hsr", NULL);
+	if (IS_ERR(hsr_debugfs_root_dir)) {
+		pr_err("Cannot create hsr debugfs root directory\n");
+		hsr_debugfs_root_dir = NULL;
+	}
+}
+
+void hsr_debugfs_remove_root(void)
+{
+	/* debugfs_remove() internally checks NULL and ERROR */
+	debugfs_remove(hsr_debugfs_root_dir);
+}
diff --git a/net/hsr/hsr_device.c b/net/hsr/hsr_device.c
index f509b49..5dd463a 100644
--- a/net/hsr/hsr_device.c
+++ b/net/hsr/hsr_device.c
@@ -227,8 +227,14 @@
 	struct hsr_port *master;
 
 	master = hsr_port_get_hsr(hsr, HSR_PT_MASTER);
-	skb->dev = master->dev;
-	hsr_forward_skb(skb, master);
+	if (master) {
+		skb->dev = master->dev;
+		skb_reset_mac_header(skb);
+		hsr_forward_skb(skb, master);
+	} else {
+		atomic_long_inc(&dev->tx_dropped);
+		dev_kfree_skb_any(skb);
+	}
 	return NETDEV_TX_OK;
 }
 
@@ -267,6 +273,8 @@
 			    skb->dev->dev_addr, skb->len) <= 0)
 		goto out;
 	skb_reset_mac_header(skb);
+	skb_reset_network_header(skb);
+	skb_reset_transport_header(skb);
 
 	if (hsr_ver > 0) {
 		hsr_tag = skb_put(skb, sizeof(struct hsr_tag));
@@ -363,7 +371,7 @@
 	del_timer_sync(&hsr->prune_timer);
 	del_timer_sync(&hsr->announce_timer);
 
-	hsr_del_self_node(&hsr->self_node_db);
+	hsr_del_self_node(hsr);
 	hsr_del_nodes(&hsr->node_db);
 }
 
@@ -435,11 +443,12 @@
 	INIT_LIST_HEAD(&hsr->ports);
 	INIT_LIST_HEAD(&hsr->node_db);
 	INIT_LIST_HEAD(&hsr->self_node_db);
+	spin_lock_init(&hsr->list_lock);
 
 	ether_addr_copy(hsr_dev->dev_addr, slave[0]->dev_addr);
 
 	/* Make sure we recognize frames from ourselves in hsr_rcv() */
-	res = hsr_create_self_node(&hsr->self_node_db, hsr_dev->dev_addr,
+	res = hsr_create_self_node(hsr, hsr_dev->dev_addr,
 				   slave[1]->dev_addr);
 	if (res < 0)
 		return res;
@@ -472,31 +481,32 @@
 
 	res = hsr_add_port(hsr, hsr_dev, HSR_PT_MASTER);
 	if (res)
-		goto err_add_port;
+		goto err_add_master;
 
 	res = register_netdevice(hsr_dev);
 	if (res)
-		goto fail;
+		goto err_unregister;
 
 	res = hsr_add_port(hsr, slave[0], HSR_PT_SLAVE_A);
 	if (res)
-		goto fail;
+		goto err_add_slaves;
+
 	res = hsr_add_port(hsr, slave[1], HSR_PT_SLAVE_B);
 	if (res)
-		goto fail;
+		goto err_add_slaves;
 
+	hsr_debugfs_init(hsr, hsr_dev);
 	mod_timer(&hsr->prune_timer, jiffies + msecs_to_jiffies(PRUNE_PERIOD));
-	res = hsr_debugfs_init(hsr, hsr_dev);
-	if (res)
-		goto fail;
 
 	return 0;
 
-fail:
+err_add_slaves:
+	unregister_netdevice(hsr_dev);
+err_unregister:
 	list_for_each_entry_safe(port, tmp, &hsr->ports, port_list)
 		hsr_del_port(port);
-err_add_port:
-	hsr_del_self_node(&hsr->self_node_db);
+err_add_master:
+	hsr_del_self_node(hsr);
 
 	return res;
 }
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c
index ddd9605..bf3ecf7 100644
--- a/net/hsr/hsr_forward.c
+++ b/net/hsr/hsr_forward.c
@@ -349,12 +349,6 @@
 {
 	struct hsr_frame_info frame;
 
-	if (skb_mac_header(skb) != skb->data) {
-		WARN_ONCE(1, "%s:%d: Malformed frame (port_src %s)\n",
-			  __FILE__, __LINE__, port->dev->name);
-		goto out_drop;
-	}
-
 	if (hsr_fill_frame_info(&frame, skb, port) < 0)
 		goto out_drop;
 	hsr_register_frame_in(frame.node_src, port, frame.sequence_nr);
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c
index 292be44..4a92007 100644
--- a/net/hsr/hsr_framereg.c
+++ b/net/hsr/hsr_framereg.c
@@ -75,10 +75,11 @@
 /* Helper for device init; the self_node_db is used in hsr_rcv() to recognize
  * frames from self that's been looped over the HSR ring.
  */
-int hsr_create_self_node(struct list_head *self_node_db,
+int hsr_create_self_node(struct hsr_priv *hsr,
 			 unsigned char addr_a[ETH_ALEN],
 			 unsigned char addr_b[ETH_ALEN])
 {
+	struct list_head *self_node_db = &hsr->self_node_db;
 	struct hsr_node *node, *oldnode;
 
 	node = kmalloc(sizeof(*node), GFP_KERNEL);
@@ -88,33 +89,33 @@
 	ether_addr_copy(node->macaddress_A, addr_a);
 	ether_addr_copy(node->macaddress_B, addr_b);
 
-	rcu_read_lock();
+	spin_lock_bh(&hsr->list_lock);
 	oldnode = list_first_or_null_rcu(self_node_db,
 					 struct hsr_node, mac_list);
 	if (oldnode) {
 		list_replace_rcu(&oldnode->mac_list, &node->mac_list);
-		rcu_read_unlock();
-		synchronize_rcu();
-		kfree(oldnode);
+		spin_unlock_bh(&hsr->list_lock);
+		kfree_rcu(oldnode, rcu_head);
 	} else {
-		rcu_read_unlock();
 		list_add_tail_rcu(&node->mac_list, self_node_db);
+		spin_unlock_bh(&hsr->list_lock);
 	}
 
 	return 0;
 }
 
-void hsr_del_self_node(struct list_head *self_node_db)
+void hsr_del_self_node(struct hsr_priv *hsr)
 {
+	struct list_head *self_node_db = &hsr->self_node_db;
 	struct hsr_node *node;
 
-	rcu_read_lock();
+	spin_lock_bh(&hsr->list_lock);
 	node = list_first_or_null_rcu(self_node_db, struct hsr_node, mac_list);
-	rcu_read_unlock();
 	if (node) {
 		list_del_rcu(&node->mac_list);
-		kfree(node);
+		kfree_rcu(node, rcu_head);
 	}
+	spin_unlock_bh(&hsr->list_lock);
 }
 
 void hsr_del_nodes(struct list_head *node_db)
@@ -130,30 +131,43 @@
  * seq_out is used to initialize filtering of outgoing duplicate frames
  * originating from the newly added node.
  */
-struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
-			      u16 seq_out)
+static struct hsr_node *hsr_add_node(struct hsr_priv *hsr,
+				     struct list_head *node_db,
+				     unsigned char addr[],
+				     u16 seq_out)
 {
-	struct hsr_node *node;
+	struct hsr_node *new_node, *node;
 	unsigned long now;
 	int i;
 
-	node = kzalloc(sizeof(*node), GFP_ATOMIC);
-	if (!node)
+	new_node = kzalloc(sizeof(*new_node), GFP_ATOMIC);
+	if (!new_node)
 		return NULL;
 
-	ether_addr_copy(node->macaddress_A, addr);
+	ether_addr_copy(new_node->macaddress_A, addr);
 
 	/* We are only interested in time diffs here, so use current jiffies
 	 * as initialization. (0 could trigger an spurious ring error warning).
 	 */
 	now = jiffies;
 	for (i = 0; i < HSR_PT_PORTS; i++)
-		node->time_in[i] = now;
+		new_node->time_in[i] = now;
 	for (i = 0; i < HSR_PT_PORTS; i++)
-		node->seq_out[i] = seq_out;
+		new_node->seq_out[i] = seq_out;
 
-	list_add_tail_rcu(&node->mac_list, node_db);
-
+	spin_lock_bh(&hsr->list_lock);
+	list_for_each_entry_rcu(node, node_db, mac_list) {
+		if (ether_addr_equal(node->macaddress_A, addr))
+			goto out;
+		if (ether_addr_equal(node->macaddress_B, addr))
+			goto out;
+	}
+	list_add_tail_rcu(&new_node->mac_list, node_db);
+	spin_unlock_bh(&hsr->list_lock);
+	return new_node;
+out:
+	spin_unlock_bh(&hsr->list_lock);
+	kfree(new_node);
 	return node;
 }
 
@@ -163,6 +177,7 @@
 			      bool is_sup)
 {
 	struct list_head *node_db = &port->hsr->node_db;
+	struct hsr_priv *hsr = port->hsr;
 	struct hsr_node *node;
 	struct ethhdr *ethhdr;
 	u16 seq_out;
@@ -196,7 +211,7 @@
 		seq_out = HSR_SEQNR_START;
 	}
 
-	return hsr_add_node(node_db, ethhdr->h_source, seq_out);
+	return hsr_add_node(hsr, node_db, ethhdr->h_source, seq_out);
 }
 
 /* Use the Supervision frame's info about an eventual macaddress_B for merging
@@ -206,10 +221,11 @@
 void hsr_handle_sup_frame(struct sk_buff *skb, struct hsr_node *node_curr,
 			  struct hsr_port *port_rcv)
 {
-	struct ethhdr *ethhdr;
-	struct hsr_node *node_real;
+	struct hsr_priv *hsr = port_rcv->hsr;
 	struct hsr_sup_payload *hsr_sp;
+	struct hsr_node *node_real;
 	struct list_head *node_db;
+	struct ethhdr *ethhdr;
 	int i;
 
 	ethhdr = (struct ethhdr *)skb_mac_header(skb);
@@ -231,7 +247,7 @@
 	node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
 	if (!node_real)
 		/* No frame received from AddrA of this node yet */
-		node_real = hsr_add_node(node_db, hsr_sp->macaddress_A,
+		node_real = hsr_add_node(hsr, node_db, hsr_sp->macaddress_A,
 					 HSR_SEQNR_START - 1);
 	if (!node_real)
 		goto done; /* No mem */
@@ -252,7 +268,9 @@
 	}
 	node_real->addr_B_port = port_rcv->type;
 
+	spin_lock_bh(&hsr->list_lock);
 	list_del_rcu(&node_curr->mac_list);
+	spin_unlock_bh(&hsr->list_lock);
 	kfree_rcu(node_curr, rcu_head);
 
 done:
@@ -300,7 +318,8 @@
 	node_dst = find_node_by_addr_A(&port->hsr->node_db,
 				       eth_hdr(skb)->h_dest);
 	if (!node_dst) {
-		WARN_ONCE(1, "%s: Unknown node\n", __func__);
+		if (net_ratelimit())
+			netdev_err(skb->dev, "%s: Unknown node\n", __func__);
 		return;
 	}
 	if (port->type != node_dst->addr_B_port)
@@ -368,12 +387,13 @@
 {
 	struct hsr_priv *hsr = from_timer(hsr, t, prune_timer);
 	struct hsr_node *node;
+	struct hsr_node *tmp;
 	struct hsr_port *port;
 	unsigned long timestamp;
 	unsigned long time_a, time_b;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(node, &hsr->node_db, mac_list) {
+	spin_lock_bh(&hsr->list_lock);
+	list_for_each_entry_safe(node, tmp, &hsr->node_db, mac_list) {
 		/* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
 		 * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
 		 * the master port. Thus the master node will be repeatedly
@@ -421,7 +441,7 @@
 			kfree_rcu(node, rcu_head);
 		}
 	}
-	rcu_read_unlock();
+	spin_unlock_bh(&hsr->list_lock);
 
 	/* Restart timer */
 	mod_timer(&hsr->prune_timer,
@@ -463,12 +483,9 @@
 	struct hsr_port *port;
 	unsigned long tdiff;
 
-	rcu_read_lock();
 	node = find_node_by_addr_A(&hsr->node_db, addr);
-	if (!node) {
-		rcu_read_unlock();
-		return -ENOENT;	/* No such entry */
-	}
+	if (!node)
+		return -ENOENT;
 
 	ether_addr_copy(addr_b, node->macaddress_B);
 
@@ -503,7 +520,5 @@
 		*addr_b_ifindex = -1;
 	}
 
-	rcu_read_unlock();
-
 	return 0;
 }
diff --git a/net/hsr/hsr_framereg.h b/net/hsr/hsr_framereg.h
index 89a3ce3..0f0fa12 100644
--- a/net/hsr/hsr_framereg.h
+++ b/net/hsr/hsr_framereg.h
@@ -12,10 +12,8 @@
 
 struct hsr_node;
 
-void hsr_del_self_node(struct list_head *self_node_db);
+void hsr_del_self_node(struct hsr_priv *hsr);
 void hsr_del_nodes(struct list_head *node_db);
-struct hsr_node *hsr_add_node(struct list_head *node_db, unsigned char addr[],
-			      u16 seq_out);
 struct hsr_node *hsr_get_node(struct hsr_port *port, struct sk_buff *skb,
 			      bool is_sup);
 void hsr_handle_sup_frame(struct sk_buff *skb, struct hsr_node *node_curr,
@@ -33,7 +31,7 @@
 
 void hsr_prune_nodes(struct timer_list *t);
 
-int hsr_create_self_node(struct list_head *self_node_db,
+int hsr_create_self_node(struct hsr_priv *hsr,
 			 unsigned char addr_a[ETH_ALEN],
 			 unsigned char addr_b[ETH_ALEN]);
 
diff --git a/net/hsr/hsr_main.c b/net/hsr/hsr_main.c
index b9988a6..9e389ac 100644
--- a/net/hsr/hsr_main.c
+++ b/net/hsr/hsr_main.c
@@ -45,6 +45,10 @@
 	case NETDEV_CHANGE:	/* Link (carrier) state changes */
 		hsr_check_carrier_and_operstate(hsr);
 		break;
+	case NETDEV_CHANGENAME:
+		if (is_hsr_master(dev))
+			hsr_debugfs_rename(dev);
+		break;
 	case NETDEV_CHANGEADDR:
 		if (port->type == HSR_PT_MASTER) {
 			/* This should not happen since there's no
@@ -64,7 +68,7 @@
 
 		/* Make sure we recognize frames from ourselves in hsr_rcv() */
 		port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
-		res = hsr_create_self_node(&hsr->self_node_db,
+		res = hsr_create_self_node(hsr,
 					   master->dev->dev_addr,
 					   port ?
 						port->dev->dev_addr :
@@ -123,6 +127,7 @@
 {
 	unregister_netdevice_notifier(&hsr_nb);
 	hsr_netlink_exit();
+	hsr_debugfs_remove_root();
 }
 
 module_init(hsr_init);
diff --git a/net/hsr/hsr_main.h b/net/hsr/hsr_main.h
index 96fac69..754d84b 100644
--- a/net/hsr/hsr_main.h
+++ b/net/hsr/hsr_main.h
@@ -160,8 +160,9 @@
 	int announce_count;
 	u16 sequence_nr;
 	u16 sup_sequence_nr;	/* For HSRv1 separate seq_nr for supervision */
-	u8 prot_version;		/* Indicate if HSRv0 or HSRv1. */
-	spinlock_t seqnr_lock;			/* locking for sequence_nr */
+	u8 prot_version;	/* Indicate if HSRv0 or HSRv1. */
+	spinlock_t seqnr_lock;	/* locking for sequence_nr */
+	spinlock_t list_lock;	/* locking for node list */
 	unsigned char		sup_multicast_addr[ETH_ALEN];
 #ifdef	CONFIG_DEBUG_FS
 	struct dentry *node_tbl_root;
@@ -184,17 +185,24 @@
 }
 
 #if IS_ENABLED(CONFIG_DEBUG_FS)
-int hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev);
+void hsr_debugfs_rename(struct net_device *dev);
+void hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev);
 void hsr_debugfs_term(struct hsr_priv *priv);
+void hsr_debugfs_create_root(void);
+void hsr_debugfs_remove_root(void);
 #else
-static inline int hsr_debugfs_init(struct hsr_priv *priv,
-				   struct net_device *hsr_dev)
+static inline void hsr_debugfs_rename(struct net_device *dev)
 {
-	return 0;
 }
-
+static inline void hsr_debugfs_init(struct hsr_priv *priv,
+				    struct net_device *hsr_dev)
+{}
 static inline void hsr_debugfs_term(struct hsr_priv *priv)
 {}
+static inline void hsr_debugfs_create_root(void)
+{}
+static inline void hsr_debugfs_remove_root(void)
+{}
 #endif
 
 #endif /*  __HSR_PRIVATE_H */
diff --git a/net/hsr/hsr_netlink.c b/net/hsr/hsr_netlink.c
index 8f8337f..55c0b2e 100644
--- a/net/hsr/hsr_netlink.c
+++ b/net/hsr/hsr_netlink.c
@@ -61,10 +61,16 @@
 	else
 		multicast_spec = nla_get_u8(data[IFLA_HSR_MULTICAST_SPEC]);
 
-	if (!data[IFLA_HSR_VERSION])
+	if (!data[IFLA_HSR_VERSION]) {
 		hsr_version = 0;
-	else
+	} else {
 		hsr_version = nla_get_u8(data[IFLA_HSR_VERSION]);
+		if (hsr_version > 1) {
+			NL_SET_ERR_MSG_MOD(extack,
+					   "Only versions 0..1 are supported");
+			return -EINVAL;
+		}
+	}
 
 	return hsr_dev_finalize(dev, link, multicast_spec, hsr_version);
 }
@@ -251,15 +257,16 @@
 	if (!na)
 		goto invalid;
 
-	hsr_dev = __dev_get_by_index(genl_info_net(info),
-				     nla_get_u32(info->attrs[HSR_A_IFINDEX]));
+	rcu_read_lock();
+	hsr_dev = dev_get_by_index_rcu(genl_info_net(info),
+				       nla_get_u32(info->attrs[HSR_A_IFINDEX]));
 	if (!hsr_dev)
-		goto invalid;
+		goto rcu_unlock;
 	if (!is_hsr_master(hsr_dev))
-		goto invalid;
+		goto rcu_unlock;
 
 	/* Send reply */
-	skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_ATOMIC);
 	if (!skb_out) {
 		res = -ENOMEM;
 		goto fail;
@@ -313,12 +320,10 @@
 	res = nla_put_u16(skb_out, HSR_A_IF1_SEQ, hsr_node_if1_seq);
 	if (res < 0)
 		goto nla_put_failure;
-	rcu_read_lock();
 	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
 	if (port)
 		res = nla_put_u32(skb_out, HSR_A_IF1_IFINDEX,
 				  port->dev->ifindex);
-	rcu_read_unlock();
 	if (res < 0)
 		goto nla_put_failure;
 
@@ -328,20 +333,22 @@
 	res = nla_put_u16(skb_out, HSR_A_IF2_SEQ, hsr_node_if2_seq);
 	if (res < 0)
 		goto nla_put_failure;
-	rcu_read_lock();
 	port = hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
 	if (port)
 		res = nla_put_u32(skb_out, HSR_A_IF2_IFINDEX,
 				  port->dev->ifindex);
-	rcu_read_unlock();
 	if (res < 0)
 		goto nla_put_failure;
 
+	rcu_read_unlock();
+
 	genlmsg_end(skb_out, msg_head);
 	genlmsg_unicast(genl_info_net(info), skb_out, info->snd_portid);
 
 	return 0;
 
+rcu_unlock:
+	rcu_read_unlock();
 invalid:
 	netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
 	return 0;
@@ -351,6 +358,7 @@
 	/* Fall through */
 
 fail:
+	rcu_read_unlock();
 	return res;
 }
 
@@ -358,16 +366,14 @@
  */
 static int hsr_get_node_list(struct sk_buff *skb_in, struct genl_info *info)
 {
-	/* For receiving */
-	struct nlattr *na;
-	struct net_device *hsr_dev;
-
-	/* For sending */
-	struct sk_buff *skb_out;
-	void *msg_head;
-	struct hsr_priv *hsr;
-	void *pos;
 	unsigned char addr[ETH_ALEN];
+	struct net_device *hsr_dev;
+	struct sk_buff *skb_out;
+	struct hsr_priv *hsr;
+	bool restart = false;
+	struct nlattr *na;
+	void *pos = NULL;
+	void *msg_head;
 	int res;
 
 	if (!info)
@@ -377,15 +383,17 @@
 	if (!na)
 		goto invalid;
 
-	hsr_dev = __dev_get_by_index(genl_info_net(info),
-				     nla_get_u32(info->attrs[HSR_A_IFINDEX]));
+	rcu_read_lock();
+	hsr_dev = dev_get_by_index_rcu(genl_info_net(info),
+				       nla_get_u32(info->attrs[HSR_A_IFINDEX]));
 	if (!hsr_dev)
-		goto invalid;
+		goto rcu_unlock;
 	if (!is_hsr_master(hsr_dev))
-		goto invalid;
+		goto rcu_unlock;
 
+restart:
 	/* Send reply */
-	skb_out = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	skb_out = genlmsg_new(GENLMSG_DEFAULT_SIZE, GFP_ATOMIC);
 	if (!skb_out) {
 		res = -ENOMEM;
 		goto fail;
@@ -399,18 +407,26 @@
 		goto nla_put_failure;
 	}
 
-	res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex);
-	if (res < 0)
-		goto nla_put_failure;
+	if (!restart) {
+		res = nla_put_u32(skb_out, HSR_A_IFINDEX, hsr_dev->ifindex);
+		if (res < 0)
+			goto nla_put_failure;
+	}
 
 	hsr = netdev_priv(hsr_dev);
 
-	rcu_read_lock();
-	pos = hsr_get_next_node(hsr, NULL, addr);
+	if (!pos)
+		pos = hsr_get_next_node(hsr, NULL, addr);
 	while (pos) {
 		res = nla_put(skb_out, HSR_A_NODE_ADDR, ETH_ALEN, addr);
 		if (res < 0) {
-			rcu_read_unlock();
+			if (res == -EMSGSIZE) {
+				genlmsg_end(skb_out, msg_head);
+				genlmsg_unicast(genl_info_net(info), skb_out,
+						info->snd_portid);
+				restart = true;
+				goto restart;
+			}
 			goto nla_put_failure;
 		}
 		pos = hsr_get_next_node(hsr, pos, addr);
@@ -422,15 +438,18 @@
 
 	return 0;
 
+rcu_unlock:
+	rcu_read_unlock();
 invalid:
 	netlink_ack(skb_in, nlmsg_hdr(skb_in), -EINVAL, NULL);
 	return 0;
 
 nla_put_failure:
-	kfree_skb(skb_out);
+	nlmsg_free(skb_out);
 	/* Fall through */
 
 fail:
+	rcu_read_unlock();
 	return res;
 }
 
@@ -457,6 +476,7 @@
 	.version = 1,
 	.maxattr = HSR_A_MAX,
 	.policy = hsr_genl_policy,
+	.netnsok = true,
 	.module = THIS_MODULE,
 	.ops = hsr_ops,
 	.n_ops = ARRAY_SIZE(hsr_ops),
@@ -476,6 +496,7 @@
 	if (rc)
 		goto fail_genl_register_family;
 
+	hsr_debugfs_create_root();
 	return 0;
 
 fail_genl_register_family:
diff --git a/net/hsr/hsr_slave.c b/net/hsr/hsr_slave.c
index ee56129..a9104d4 100644
--- a/net/hsr/hsr_slave.c
+++ b/net/hsr/hsr_slave.c
@@ -27,6 +27,8 @@
 
 	rcu_read_lock(); /* hsr->node_db, hsr->ports */
 	port = hsr_port_get_rcu(skb->dev);
+	if (!port)
+		goto finish_pass;
 
 	if (hsr_addr_is_self(port->hsr, eth_hdr(skb)->h_source)) {
 		/* Directly kill frames sent by ourselves */
@@ -143,16 +145,16 @@
 	if (!port)
 		return -ENOMEM;
 
+	port->hsr = hsr;
+	port->dev = dev;
+	port->type = type;
+
 	if (type != HSR_PT_MASTER) {
 		res = hsr_portdev_setup(dev, port);
 		if (res)
 			goto fail_dev_setup;
 	}
 
-	port->hsr = hsr;
-	port->dev = dev;
-	port->type = type;
-
 	list_add_tail_rcu(&port->port_list, &hsr->ports);
 	synchronize_rcu();