Merge branch 'ip-random-cleanup-for-devinet-c'

Kuniyuki Iwashima says:

====================
ip: Random cleanup for devinet.c

patch 1 ~ 3 remove defensive !ifa->ifa_dev tests.
patch 4 & 5 deduplicate common code.
====================

Link: https://patch.msgid.link/20240809235406.50187-1-kuniyu@amazon.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/qlogic/netxen/netxen_nic_main.c

@@ -3185,8 +3185,7 @@ netxen_list_config_ip(struct netxen_adapter *adapter,
 	struct list_head *head;
 	bool ret = false;
 
-	dev = ifa->ifa_dev ? ifa->ifa_dev->dev : NULL;
-
+	dev = ifa->ifa_dev->dev;
 	if (dev == NULL)
 		goto out;
 
@@ -3379,7 +3378,7 @@ netxen_inetaddr_event(struct notifier_block *this,
 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
 	unsigned long ip_event;
 
-	dev = ifa->ifa_dev ? ifa->ifa_dev->dev : NULL;
+	dev = ifa->ifa_dev->dev;
 	ip_event = (event == NETDEV_UP) ? NX_IP_UP : NX_IP_DOWN;
 recheck:
 	if (dev == NULL)

drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c

@@ -4146,7 +4146,7 @@ qlcnic_inetaddr_event(struct notifier_block *this,
 
 	struct in_ifaddr *ifa = (struct in_ifaddr *)ptr;
 
-	dev = ifa->ifa_dev ? ifa->ifa_dev->dev : NULL;
+	dev = ifa->ifa_dev->dev;
 
 recheck:
 	if (dev == NULL)

include/net/addrconf.h

@@ -187,10 +187,12 @@ static inline int addrconf_ifid_eui48(u8 *eui, struct net_device *dev)
 	return 0;
 }
 
+#define INFINITY_LIFE_TIME 0xFFFFFFFF
+
 static inline unsigned long addrconf_timeout_fixup(u32 timeout,
 						   unsigned int unit)
 {
-	if (timeout == 0xffffffff)
+	if (timeout == INFINITY_LIFE_TIME)
 		return ~0UL;
 
 	/*

net/ipv4/devinet.c

@@ -216,17 +216,27 @@ static void devinet_sysctl_unregister(struct in_device *idev)
 
 /* Locks all the inet devices. */
 
-static struct in_ifaddr *inet_alloc_ifa(void)
+static struct in_ifaddr *inet_alloc_ifa(struct in_device *in_dev)
 {
-	return kzalloc(sizeof(struct in_ifaddr), GFP_KERNEL_ACCOUNT);
+	struct in_ifaddr *ifa;
+
+	ifa = kzalloc(sizeof(*ifa), GFP_KERNEL_ACCOUNT);
+	if (!ifa)
+		return NULL;
+
+	in_dev_hold(in_dev);
+	ifa->ifa_dev = in_dev;
+
+	INIT_HLIST_NODE(&ifa->hash);
+
+	return ifa;
 }
 
 static void inet_rcu_free_ifa(struct rcu_head *head)
 {
 	struct in_ifaddr *ifa = container_of(head, struct in_ifaddr, rcu_head);
 
-	if (ifa->ifa_dev)
-		in_dev_put(ifa->ifa_dev);
+	in_dev_put(ifa->ifa_dev);
 	kfree(ifa);
 }
 
@@ -574,17 +584,9 @@ static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa)
 
 	ASSERT_RTNL();
 
-	if (!in_dev) {
-		inet_free_ifa(ifa);
-		return -ENOBUFS;
-	}
 	ipv4_devconf_setall(in_dev);
 	neigh_parms_data_state_setall(in_dev->arp_parms);
-	if (ifa->ifa_dev != in_dev) {
-		WARN_ON(ifa->ifa_dev);
-		in_dev_hold(in_dev);
-		ifa->ifa_dev = in_dev;
-	}
+
 	if (ipv4_is_loopback(ifa->ifa_local))
 		ifa->ifa_scope = RT_SCOPE_HOST;
 	return inet_insert_ifa(ifa);
@@ -701,8 +703,6 @@ static int inet_rtm_deladdr(struct sk_buff *skb, struct nlmsghdr *nlh,
 	return err;
 }
 
-#define INFINITY_LIFE_TIME	0xFFFFFFFF
-
 static void check_lifetime(struct work_struct *work)
 {
 	unsigned long now, next, next_sec, next_sched;
@@ -875,7 +875,7 @@ static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
 	if (!in_dev)
 		goto errout;
 
-	ifa = inet_alloc_ifa();
+	ifa = inet_alloc_ifa(in_dev);
 	if (!ifa)
 		/*
 		 * A potential indev allocation can be left alive, it stays
@@ -885,19 +885,15 @@ static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh,
 
 	ipv4_devconf_setall(in_dev);
 	neigh_parms_data_state_setall(in_dev->arp_parms);
-	in_dev_hold(in_dev);
 
 	if (!tb[IFA_ADDRESS])
 		tb[IFA_ADDRESS] = tb[IFA_LOCAL];
 
-	INIT_HLIST_NODE(&ifa->hash);
 	ifa->ifa_prefixlen = ifm->ifa_prefixlen;
 	ifa->ifa_mask = inet_make_mask(ifm->ifa_prefixlen);
 	ifa->ifa_flags = tb[IFA_FLAGS] ? nla_get_u32(tb[IFA_FLAGS]) :
 					 ifm->ifa_flags;
 	ifa->ifa_scope = ifm->ifa_scope;
-	ifa->ifa_dev = in_dev;
-
 	ifa->ifa_local = nla_get_in_addr(tb[IFA_LOCAL]);
 	ifa->ifa_address = nla_get_in_addr(tb[IFA_ADDRESS]);
 
@@ -1184,10 +1180,12 @@ int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr)
 
 		if (!ifa) {
 			ret = -ENOBUFS;
-			ifa = inet_alloc_ifa();
+			if (!in_dev)
+				break;
+			ifa = inet_alloc_ifa(in_dev);
 			if (!ifa)
 				break;
-			INIT_HLIST_NODE(&ifa->hash);
+
 			if (colon)
 				memcpy(ifa->ifa_label, ifr->ifr_name, IFNAMSIZ);
 			else
@@ -1586,16 +1584,13 @@ static int inetdev_event(struct notifier_block *this, unsigned long event,
 		if (!inetdev_valid_mtu(dev->mtu))
 			break;
 		if (dev->flags & IFF_LOOPBACK) {
-			struct in_ifaddr *ifa = inet_alloc_ifa();
+			struct in_ifaddr *ifa = inet_alloc_ifa(in_dev);
 
 			if (ifa) {
-				INIT_HLIST_NODE(&ifa->hash);
 				ifa->ifa_local =
 				  ifa->ifa_address = htonl(INADDR_LOOPBACK);
 				ifa->ifa_prefixlen = 8;
 				ifa->ifa_mask = inet_make_mask(8);
-				in_dev_hold(in_dev);
-				ifa->ifa_dev = in_dev;
 				ifa->ifa_scope = RT_SCOPE_HOST;
 				memcpy(ifa->ifa_label, dev->name, IFNAMSIZ);
 				set_ifa_lifetime(ifa, INFINITY_LIFE_TIME,

net/ipv6/addrconf.c

@@ -92,8 +92,6 @@
 #include <linux/export.h>
 #include <linux/ioam6.h>
 
-#define	INFINITY_LIFE_TIME	0xFFFFFFFF
-
 #define IPV6_MAX_STRLEN \
 	sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")