switchdev: assert rtnl mutex when going over lower netdevs

netdev_for_each_lower_dev has to be called with rtnl mutex held. So
better enforce it in switchdev functions.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index eac68c4e57ec..73e3895175cf 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -520,6 +520,8 @@ EXPORT_SYMBOL_GPL(switchdev_port_obj_del);
  *      @id: object ID
  *      @obj: object to dump
  *      @cb: function to call with a filled object
+ *
+ *      rtnl_lock must be held.
  */
 int switchdev_port_obj_dump(struct net_device *dev, struct switchdev_obj *obj,
                             switchdev_obj_dump_cb_t *cb)
@@ -529,6 +531,8 @@ int switchdev_port_obj_dump(struct net_device *dev, struct switchdev_obj *obj,
         struct list_head *iter;
         int err = -EOPNOTSUPP;
 
+        ASSERT_RTNL();
+
         if (ops && ops->switchdev_port_obj_dump)
                 return ops->switchdev_port_obj_dump(dev, obj, cb);
 
@@ -1097,6 +1101,8 @@ static struct net_device *switchdev_get_dev_by_nhs(struct fib_info *fi)
         struct net_device *dev = NULL;
         int nhsel;
 
+        ASSERT_RTNL();
+
         /* For this route, all nexthop devs must be on the same switch. */
 
         for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) {
@@ -1327,10 +1333,11 @@ void switchdev_port_fwd_mark_set(struct net_device *dev,
         u32 mark = dev->ifindex;
         u32 reset_mark = 0;
 
-        if (group_dev && joining) {
-                mark = switchdev_port_fwd_mark_get(dev, group_dev);
-        } else if (group_dev && !joining) {
-                if (dev->offload_fwd_mark == mark)
+        if (group_dev) {
+                ASSERT_RTNL();
+                if (joining)
+                        mark = switchdev_port_fwd_mark_get(dev, group_dev);
+                else if (dev->offload_fwd_mark == mark)
                         /* Ohoh, this port was the mark reference port,
                          * but it's leaving the group, so reset the
                          * mark for the remaining ports in the group.