net: dev_close() should check IFF_UP
authorEric Dumazet <eric.dumazet@gmail.com>
Tue, 10 May 2011 19:26:06 +0000 (12:26 -0700)
committerDavid S. Miller <davem@davemloft.net>
Tue, 10 May 2011 22:03:33 +0000 (15:03 -0700)
Commit 443457242beb (factorize sync-rcu call in
unregister_netdevice_many) mistakenly removed one test from dev_close()

Following actions trigger a BUG :

modprobe bonding
modprobe dummy
ifconfig bond0 up
ifenslave bond0 dummy0
rmmod dummy

dev_close() must not close a non IFF_UP device.

With help from Frank Blaschka and Einar EL Lueck

Reported-by: Frank Blaschka <blaschka@linux.vnet.ibm.com>
Reported-by: Einar EL Lueck <ELELUECK@de.ibm.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/core/dev.c

index 856b6ee..9200944 100644 (file)
@@ -1284,11 +1284,13 @@ static int dev_close_many(struct list_head *head)
  */
 int dev_close(struct net_device *dev)
 {
-       LIST_HEAD(single);
+       if (dev->flags & IFF_UP) {
+               LIST_HEAD(single);
 
-       list_add(&dev->unreg_list, &single);
-       dev_close_many(&single);
-       list_del(&single);
+               list_add(&dev->unreg_list, &single);
+               dev_close_many(&single);
+               list_del(&single);
+       }
        return 0;
 }
 EXPORT_SYMBOL(dev_close);