diff options
| author | Petr Machata <petrm@mellanox.com> | 2018-12-18 13:16:00 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2018-12-18 21:18:25 -0800 |
| commit | 6db9246871394b3a136cd52001a0763676563840 (patch) | |
| tree | 7b146c9acfe3cafbc4c2a1b9dea8853d7491e8d0 | |
| parent | 6ad0b5a4e03dc5cc0c1ed6be093bdcefdc794a6f (diff) | |
vxlan: Fix error path in __vxlan_dev_create()
When a failure occurs in rtnl_configure_link(), the current code
calls unregister_netdevice() to roll back the earlier call to
register_netdevice(), and jumps to errout, which calls
vxlan_fdb_destroy().
However unregister_netdevice() calls transitively ndo_uninit, which is
vxlan_uninit(), and that already takes care of deleting the default FDB
entry by calling vxlan_fdb_delete_default(). Since the entry added
earlier in __vxlan_dev_create() is exactly the default entry, the
cleanup code in the errout block always leads to double free and thus a
panic.
Besides, since vxlan_fdb_delete_default() always destroys the FDB entry
with notification enabled, the deletion of the default entry is notified
even before the addition was notified.
Instead, move the unregister_netdevice() call after the manual destroy,
which solves both problems.
Fixes: 0241b836732f ("vxlan: fix default fdb entry netlink notify ordering during netdev create")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/vxlan.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index c9956c08edf5..82e78d6fd9ae 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -3259,6 +3259,7 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, struct vxlan_net *vn = net_generic(net, vxlan_net_id); struct vxlan_dev *vxlan = netdev_priv(dev); struct vxlan_fdb *f = NULL; + bool unregister = false; int err; err = vxlan_dev_configure(net, dev, conf, false, extack); @@ -3284,12 +3285,11 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, err = register_netdevice(dev); if (err) goto errout; + unregister = true; err = rtnl_configure_link(dev, NULL); - if (err) { - unregister_netdevice(dev); + if (err) goto errout; - } /* notify default fdb entry */ if (f) @@ -3297,9 +3297,16 @@ static int __vxlan_dev_create(struct net *net, struct net_device *dev, list_add(&vxlan->next, &vn->vxlan_list); return 0; + errout: + /* unregister_netdevice() destroys the default FDB entry with deletion + * notification. But the addition notification was not sent yet, so + * destroy the entry by hand here. + */ if (f) vxlan_fdb_destroy(vxlan, f, false); + if (unregister) + unregister_netdevice(dev); return err; } |