netback: don't store invalid vif pointer

When xenvif_alloc() fails, it returns a non-NULL error indicator. To
avoid eventual races, we shouldn't store that into struct backend_info
as readers of it only check for NULL.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Jan Beulich 2014-12-09 11:47:04 +00:00 committed by David S. Miller
parent ceaca9dc3c
commit f15650b7f9

View File

@ -404,6 +404,7 @@ static int backend_create_xenvif(struct backend_info *be)
int err;
long handle;
struct xenbus_device *dev = be->dev;
struct xenvif *vif;
if (be->vif != NULL)
return 0;
@ -414,13 +415,13 @@ static int backend_create_xenvif(struct backend_info *be)
return (err < 0) ? err : -EINVAL;
}
be->vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
if (IS_ERR(be->vif)) {
err = PTR_ERR(be->vif);
be->vif = NULL;
vif = xenvif_alloc(&dev->dev, dev->otherend_id, handle);
if (IS_ERR(vif)) {
err = PTR_ERR(vif);
xenbus_dev_fatal(dev, err, "creating interface");
return err;
}
be->vif = vif;
kobject_uevent(&dev->dev.kobj, KOBJ_ONLINE);
return 0;