Merge branch 'ipvlan-addrs_lock-made-per-port'

Dmitry Skorodumov says:

====================
ipvlan: addrs_lock made per port

First patch fixes a rather minor issues that sometimes
ipvlan-addrs are modified without lock (because
for IPv6 addr can be sometimes added without RTNL)
====================

Link: https://patch.msgid.link/20260112142417.4039566-1-skorodumov.dmitry@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

Author: kuba-moo

drivers/net/ipvlan/ipvlan.h

@@ -69,7 +69,6 @@ struct ipvl_dev {
 	DECLARE_BITMAP(mac_filters, IPVLAN_MAC_FILTER_SIZE);
 	netdev_features_t	sfeatures;
 	u32			msg_enable;
-	spinlock_t		addrs_lock;
 };
 
 struct ipvl_addr {
@@ -90,6 +89,7 @@ struct ipvl_port {
 	struct net_device	*dev;
 	possible_net_t		pnet;
 	struct hlist_head	hlhead[IPVLAN_HASH_SIZE];
+	spinlock_t		addrs_lock; /* guards hash-table and addrs */
 	struct list_head	ipvlans;
 	u16			mode;
 	u16			flags;

drivers/net/ipvlan/ipvlan_core.c

@@ -107,17 +107,15 @@ void ipvlan_ht_addr_del(struct ipvl_addr *addr)
 struct ipvl_addr *ipvlan_find_addr(const struct ipvl_dev *ipvlan,
 				   const void *iaddr, bool is_v6)
 {
-	struct ipvl_addr *addr, *ret = NULL;
+	struct ipvl_addr *addr;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(addr, &ipvlan->addrs, anode) {
-		if (addr_equal(is_v6, addr, iaddr)) {
-			ret = addr;
-			break;
-		}
+	assert_spin_locked(&ipvlan->port->addrs_lock);
+
+	list_for_each_entry(addr, &ipvlan->addrs, anode) {
+		if (addr_equal(is_v6, addr, iaddr))
+			return addr;
 	}
-	rcu_read_unlock();
-	return ret;
+	return NULL;
 }
 
 bool ipvlan_addr_busy(struct ipvl_port *port, void *iaddr, bool is_v6)

drivers/net/ipvlan/ipvlan_main.c

@@ -75,6 +75,7 @@ static int ipvlan_port_create(struct net_device *dev)
 	for (idx = 0; idx < IPVLAN_HASH_SIZE; idx++)
 		INIT_HLIST_HEAD(&port->hlhead[idx]);
 
+	spin_lock_init(&port->addrs_lock);
 	skb_queue_head_init(&port->backlog);
 	INIT_WORK(&port->wq, ipvlan_process_multicast);
 	ida_init(&port->ida);
@@ -181,6 +182,7 @@ static void ipvlan_uninit(struct net_device *dev)
 static int ipvlan_open(struct net_device *dev)
 {
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
+	struct ipvl_port *port = ipvlan->port;
 	struct ipvl_addr *addr;
 
 	if (ipvlan->port->mode == IPVLAN_MODE_L3 ||
@@ -189,10 +191,10 @@ static int ipvlan_open(struct net_device *dev)
 	else
 		dev->flags &= ~IFF_NOARP;
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(addr, &ipvlan->addrs, anode)
+	spin_lock_bh(&port->addrs_lock);
+	list_for_each_entry(addr, &ipvlan->addrs, anode)
 		ipvlan_ht_addr_add(ipvlan, addr);
-	rcu_read_unlock();
+	spin_unlock_bh(&port->addrs_lock);
 
 	return 0;
 }
@@ -206,10 +208,10 @@ static int ipvlan_stop(struct net_device *dev)
 	dev_uc_unsync(phy_dev, dev);
 	dev_mc_unsync(phy_dev, dev);
 
-	rcu_read_lock();
-	list_for_each_entry_rcu(addr, &ipvlan->addrs, anode)
+	spin_lock_bh(&ipvlan->port->addrs_lock);
+	list_for_each_entry(addr, &ipvlan->addrs, anode)
 		ipvlan_ht_addr_del(addr);
-	rcu_read_unlock();
+	spin_unlock_bh(&ipvlan->port->addrs_lock);
 
 	return 0;
 }
@@ -579,7 +581,6 @@ int ipvlan_link_new(struct net_device *dev, struct rtnl_newlink_params *params,
 	if (!tb[IFLA_MTU])
 		ipvlan_adjust_mtu(ipvlan, phy_dev);
 	INIT_LIST_HEAD(&ipvlan->addrs);
-	spin_lock_init(&ipvlan->addrs_lock);
 
 	/* TODO Probably put random address here to be presented to the
 	 * world but keep using the physical-dev address for the outgoing
@@ -657,13 +658,13 @@ void ipvlan_link_delete(struct net_device *dev, struct list_head *head)
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
 	struct ipvl_addr *addr, *next;
 
-	spin_lock_bh(&ipvlan->addrs_lock);
+	spin_lock_bh(&ipvlan->port->addrs_lock);
 	list_for_each_entry_safe(addr, next, &ipvlan->addrs, anode) {
 		ipvlan_ht_addr_del(addr);
 		list_del_rcu(&addr->anode);
 		kfree_rcu(addr, rcu);
 	}
-	spin_unlock_bh(&ipvlan->addrs_lock);
+	spin_unlock_bh(&ipvlan->port->addrs_lock);
 
 	ida_free(&ipvlan->port->ida, dev->dev_id);
 	list_del_rcu(&ipvlan->pnode);
@@ -817,6 +818,8 @@ static int ipvlan_add_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
 {
 	struct ipvl_addr *addr;
 
+	assert_spin_locked(&ipvlan->port->addrs_lock);
+
 	addr = kzalloc(sizeof(struct ipvl_addr), GFP_ATOMIC);
 	if (!addr)
 		return -ENOMEM;
@@ -847,16 +850,16 @@ static void ipvlan_del_addr(struct ipvl_dev *ipvlan, void *iaddr, bool is_v6)
 {
 	struct ipvl_addr *addr;
 
-	spin_lock_bh(&ipvlan->addrs_lock);
+	spin_lock_bh(&ipvlan->port->addrs_lock);
 	addr = ipvlan_find_addr(ipvlan, iaddr, is_v6);
 	if (!addr) {
-		spin_unlock_bh(&ipvlan->addrs_lock);
+		spin_unlock_bh(&ipvlan->port->addrs_lock);
 		return;
 	}
 
 	ipvlan_ht_addr_del(addr);
 	list_del_rcu(&addr->anode);
-	spin_unlock_bh(&ipvlan->addrs_lock);
+	spin_unlock_bh(&ipvlan->port->addrs_lock);
 	kfree_rcu(addr, rcu);
 }
 
@@ -878,14 +881,14 @@ static int ipvlan_add_addr6(struct ipvl_dev *ipvlan, struct in6_addr *ip6_addr)
 {
 	int ret = -EINVAL;
 
-	spin_lock_bh(&ipvlan->addrs_lock);
+	spin_lock_bh(&ipvlan->port->addrs_lock);
 	if (ipvlan_addr_busy(ipvlan->port, ip6_addr, true))
 		netif_err(ipvlan, ifup, ipvlan->dev,
 			  "Failed to add IPv6=%pI6c addr for %s intf\n",
 			  ip6_addr, ipvlan->dev->name);
 	else
 		ret = ipvlan_add_addr(ipvlan, ip6_addr, true);
-	spin_unlock_bh(&ipvlan->addrs_lock);
+	spin_unlock_bh(&ipvlan->port->addrs_lock);
 	return ret;
 }
 
@@ -924,36 +927,39 @@ static int ipvlan_addr6_validator_event(struct notifier_block *unused,
 	struct in6_validator_info *i6vi = (struct in6_validator_info *)ptr;
 	struct net_device *dev = (struct net_device *)i6vi->i6vi_dev->dev;
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
+	int ret = NOTIFY_OK;
 
 	if (!ipvlan_is_valid_dev(dev))
 		return NOTIFY_DONE;
 
 	switch (event) {
 	case NETDEV_UP:
+		spin_lock_bh(&ipvlan->port->addrs_lock);
 		if (ipvlan_addr_busy(ipvlan->port, &i6vi->i6vi_addr, true)) {
 			NL_SET_ERR_MSG(i6vi->extack,
 				       "Address already assigned to an ipvlan device");
-			return notifier_from_errno(-EADDRINUSE);
+			ret = notifier_from_errno(-EADDRINUSE);
 		}
+		spin_unlock_bh(&ipvlan->port->addrs_lock);
 		break;
 	}
 
-	return NOTIFY_OK;
+	return ret;
 }
 #endif
 
 static int ipvlan_add_addr4(struct ipvl_dev *ipvlan, struct in_addr *ip4_addr)
 {
 	int ret = -EINVAL;
 
-	spin_lock_bh(&ipvlan->addrs_lock);
+	spin_lock_bh(&ipvlan->port->addrs_lock);
 	if (ipvlan_addr_busy(ipvlan->port, ip4_addr, false))
 		netif_err(ipvlan, ifup, ipvlan->dev,
 			  "Failed to add IPv4=%pI4 on %s intf.\n",
 			  ip4_addr, ipvlan->dev->name);
 	else
 		ret = ipvlan_add_addr(ipvlan, ip4_addr, false);
-	spin_unlock_bh(&ipvlan->addrs_lock);
+	spin_unlock_bh(&ipvlan->port->addrs_lock);
 	return ret;
 }
 
@@ -995,21 +1001,24 @@ static int ipvlan_addr4_validator_event(struct notifier_block *unused,
 	struct in_validator_info *ivi = (struct in_validator_info *)ptr;
 	struct net_device *dev = (struct net_device *)ivi->ivi_dev->dev;
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
+	int ret = NOTIFY_OK;
 
 	if (!ipvlan_is_valid_dev(dev))
 		return NOTIFY_DONE;
 
 	switch (event) {
 	case NETDEV_UP:
+		spin_lock_bh(&ipvlan->port->addrs_lock);
 		if (ipvlan_addr_busy(ipvlan->port, &ivi->ivi_addr, false)) {
 			NL_SET_ERR_MSG(ivi->extack,
 				       "Address already assigned to an ipvlan device");
-			return notifier_from_errno(-EADDRINUSE);
+			ret = notifier_from_errno(-EADDRINUSE);
 		}
+		spin_unlock_bh(&ipvlan->port->addrs_lock);
 		break;
 	}
 
-	return NOTIFY_OK;
+	return ret;
 }
 
 static struct notifier_block ipvlan_addr4_notifier_block __read_mostly = {

tools/testing/selftests/net/Makefile

@@ -48,6 +48,7 @@ TEST_PROGS := \
 	ipv6_flowlabel.sh \
 	ipv6_force_forwarding.sh \
 	ipv6_route_update_soft_lockup.sh \
+	ipvtap_test.sh \
 	l2_tos_ttl_inherit.sh \
 	l2tp.sh \
 	link_netns.py \

tools/testing/selftests/net/config

@@ -48,6 +48,7 @@ CONFIG_IPV6_SEG6_LWTUNNEL=y
 CONFIG_IPV6_SIT=y
 CONFIG_IPV6_VTI=y
 CONFIG_IPVLAN=m
+CONFIG_IPVTAP=m
 CONFIG_KALLSYMS=y
 CONFIG_L2TP=m
 CONFIG_L2TP_ETH=m
@@ -116,6 +117,7 @@ CONFIG_PROC_SYSCTL=y
 CONFIG_PSAMPLE=m
 CONFIG_RPS=y
 CONFIG_SYSFS=y
+CONFIG_TAP=m
 CONFIG_TCP_MD5SIG=y
 CONFIG_TEST_BLACKHOLE_DEV=m
 CONFIG_TEST_BPF=m