Commit 6e701eb9 authored by Kuniyuki Iwashima's avatar Kuniyuki Iwashima Committed by Jakub Kicinski
Browse files

ipv4: Set ifa->ifa_dev in inet_alloc_ifa(). 



When a new IPv4 address is assigned via ioctl(SIOCSIFADDR),
inet_set_ifa() sets ifa->ifa_dev if it's different from in_dev
passed as an argument.

In this case, ifa is always a newly allocated object, and
ifa->ifa_dev is NULL.

inet_set_ifa() can be called for an existing reused ifa, then,
this check is always false.

Let's set ifa_dev in inet_alloc_ifa() and remove the check
in inet_set_ifa().

Now, inet_alloc_ifa() is symmetric with inet_rcu_free_ifa().

Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@amazon.com>
Link: https://patch.msgid.link/20240809235406.50187-3-kuniyu@amazon.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent e3af3d3c

net/ipv4/devinet.c

+15 −15
Original line number Diff line number Diff line
@@ -216,9 +216,18 @@ 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;



	return ifa;

}



static void inet_rcu_free_ifa(struct rcu_head *head)
@@ -576,11 +585,7 @@ static int inet_set_ifa(struct net_device *dev, struct in_ifaddr *ifa) 


	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);
@@ -871,7 +876,7 @@ 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
@@ -881,7 +886,6 @@ 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];
@@ -892,8 +896,6 @@ static struct in_ifaddr *rtm_to_ifaddr(struct net *net, struct nlmsghdr *nlh, 
	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]);
@@ -1182,7 +1184,7 @@ int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *ifr) 
			ret = -ENOBUFS;

			if (!in_dev)

				break;

			ifa = inet_alloc_ifa();

			ifa = inet_alloc_ifa(in_dev);

			if (!ifa)

				break;

			INIT_HLIST_NODE(&ifa->hash);
@@ -1584,7 +1586,7 @@ 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);
@@ -1592,8 +1594,6 @@ static int inetdev_event(struct notifier_block *this, unsigned long event, 
				  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,