bonding: avoid adding slave device with IFF_MASTER flag

mainline-inclusion
from mainline-v5.16-rc7
commit 3c9ef511
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I4RADY
CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=3c9ef511b9fa128a4c62e3aa0aac4c6b190f0d55

-------------------------------------------------

The following steps will definitely cause the kernel to crash:
	ip link add vrf1 type vrf table 1
	modprobe bonding.ko max_bonds=1
	echo "+vrf1" >/sys/class/net/bond0/bonding/slaves
	rmmod bonding

The root cause is that: When the VRF is added to the slave device,
it will fail, and some cleaning work will be done. because VRF device
has IFF_MASTER flag, cleanup process  will not clear the IFF_BONDING flag.
Then, when we unload the bonding module, unregister_netdevice_notifier()
will treat the VRF device as a bond master device and treat netdev_priv()
as struct bonding{} which actually is struct net_vrf{}.

By analyzing the processing logic of bond_enslave(), it seems that
it is not allowed to add the slave device with the IFF_MASTER flag, so
we need to add a code check for this situation.
Signed-off-by: NDi Zhu <zhudi21@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NAichun Li <liaichun@huawei.com>
Signed-off-by: NAichun Li <liaichun@huawei.com>
Reviewed-by: NYue Haibing <yuehaibing@huawei.com>
Reviewed-by: Nwuchangye <wuchangye@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

drivers/net/bonding/bond_main.c

@@ -1700,6 +1700,12 @@ int bond_enslave(struct net_device *bond_dev, struct net_device *slave_dev,
 	int link_reporting;
 	int res = 0, i;
 
+	if (slave_dev->flags & IFF_MASTER) {
+		netdev_err(bond_dev,
+			   "Error: Device with IFF_MASTER cannot be enslaved\n");
+		return -EPERM;
+	}
+
 	if (!bond->params.use_carrier &&
 	    slave_dev->ethtool_ops->get_link == NULL &&
 	    slave_ops->ndo_do_ioctl == NULL) {