Merge tag 'imx-drm-fixes-2017-07-18' of git://git.pengutronix.de/git/pza/linux into...

[mirror_ubuntu-bionic-kernel.git] / net / ipv4 / devinet.c

diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c
index df14815a3b8ce74aeb613458ffaf5f6eee4a263d..38d9af9b917c08685deb3288baab84189ec9c9a0 100644 (file)
--- a/net/ipv4/devinet.c
+++ b/net/ipv4/devinet.c
@@ -176,6 +176,7 @@ EXPORT_SYMBOL(__ip_dev_find);
 static void rtmsg_ifa(int event, struct in_ifaddr *, struct nlmsghdr *, u32);
 
 static BLOCKING_NOTIFIER_HEAD(inetaddr_chain);
+static BLOCKING_NOTIFIER_HEAD(inetaddr_validator_chain);
 static void inet_del_ifa(struct in_device *in_dev, struct in_ifaddr **ifap,
                         int destroy);
 #ifdef CONFIG_SYSCTL
@@ -251,7 +252,7 @@ static struct in_device *inetdev_init(struct net_device *dev)
        /* Reference in_dev->dev */
        dev_hold(dev);
        /* Account for reference dev->ip_ptr (below) */
-       in_dev_hold(in_dev);
+       refcount_set(&in_dev->refcnt, 1);
 
        err = devinet_sysctl_register(in_dev);
        if (err) {
@@ -441,6 +442,8 @@ static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
 {
        struct in_device *in_dev = ifa->ifa_dev;
        struct in_ifaddr *ifa1, **ifap, **last_primary;
+       struct in_validator_info ivi;
+       int ret;
 
        ASSERT_RTNL();
 
@@ -471,6 +474,23 @@ static int __inet_insert_ifa(struct in_ifaddr *ifa, struct nlmsghdr *nlh,
                }
        }
 
+       /* Allow any devices that wish to register ifaddr validtors to weigh
+        * in now, before changes are committed.  The rntl lock is serializing
+        * access here, so the state should not change between a validator call
+        * and a final notify on commit.  This isn't invoked on promotion under
+        * the assumption that validators are checking the address itself, and
+        * not the flags.
+        */
+       ivi.ivi_addr = ifa->ifa_address;
+       ivi.ivi_dev = ifa->ifa_dev;
+       ret = blocking_notifier_call_chain(&inetaddr_validator_chain,
+                                          NETDEV_UP, &ivi);
+       ret = notifier_to_errno(ret);
+       if (ret) {
+               inet_free_ifa(ifa);
+               return ret;
+       }
+
        if (!(ifa->ifa_flags & IFA_F_SECONDARY)) {
                prandom_seed((__force u32) ifa->ifa_local);
                ifap = last_primary;
@@ -1356,6 +1376,19 @@ int unregister_inetaddr_notifier(struct notifier_block *nb)
 }
 EXPORT_SYMBOL(unregister_inetaddr_notifier);
 
+int register_inetaddr_validator_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_register(&inetaddr_validator_chain, nb);
+}
+EXPORT_SYMBOL(register_inetaddr_validator_notifier);
+
+int unregister_inetaddr_validator_notifier(struct notifier_block *nb)
+{
+       return blocking_notifier_chain_unregister(&inetaddr_validator_chain,
+           nb);
+}
+EXPORT_SYMBOL(unregister_inetaddr_validator_notifier);
+
 /* Rename ifa_labels for a device name change. Make some effort to preserve
  * existing alias numbering and to create unique labels if possible.
 */