bonding: disallow enslaving a bond to itself

Enslaving a bond to itself leads to an endless loop and hangs the kernel.

Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Tested-by: Ding Tianhong <dingtianhong@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index b47fa0421e01..e5628fc725c3 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1197,6 +1197,11 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev)
                 return -EBUSY;
         }
 
+        if (bond_dev == slave_dev) {
+                pr_err("%s: cannot enslave bond to itself.\n", bond_dev->name);
+                return -EPERM;
+        }
+
         /* vlan challenged mutual exclusion */
         /* no need to lock since we're protected by rtnl_lock */
         if (slave_dev->features & NETIF_F_VLAN_CHALLENGED) {