[IPV6]: Track device renames in snmp6.

When network device's are renamed, the IPV6 snmp6 code
gets confused. It doesn't track name changes so it will OOPS
when network device's are removed.

The fix is trivial, just unregister/re-register in notify handler.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 5 insertions, 2 deletions

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index e04e49373505..3452433cbc96 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -2359,8 +2359,9 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event,
                 break;
 
         case NETDEV_CHANGENAME:
-#ifdef CONFIG_SYSCTL
                 if (idev) {
+                        snmp6_unregister_dev(idev);
+#ifdef CONFIG_SYSCTL
                         addrconf_sysctl_unregister(&idev->cnf);
                         neigh_sysctl_unregister(idev->nd_parms);
                         neigh_sysctl_register(dev, idev->nd_parms,
@@ -2368,8 +2369,9 @@ static int addrconf_notify(struct notifier_block *this, unsigned long event,
                                               &ndisc_ifinfo_sysctl_change,
                                               NULL);
                         addrconf_sysctl_register(idev, &idev->cnf);
-                }
 #endif
+                        snmp6_register_dev(idev);
+                }
                 break;
         }
 
diff --git a/net/ipv6/proc.c b/net/ipv6/proc.c
index acb306a5dd56..920dc9cf6a84 100644
--- a/net/ipv6/proc.c
+++ b/net/ipv6/proc.c
@@ -223,6 +223,7 @@ int snmp6_unregister_dev(struct inet6_dev *idev)
                 return -EINVAL;
         remove_proc_entry(idev->stats.proc_dir_entry->name,
                           proc_net_devsnmp6);
+        idev->stats.proc_dir_entry = NULL;
         return 0;
 }