macvtap: Ignore tap features when VNET_HDR is off

[~andy/linux] / drivers / net / macvtap.c

diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c
index b51db2abfe442cd95fdbcb97e17aec702ec0d2c5..ea53abb209889ed1032323bfcebd154e68fc1d1d 100644 (file)
--- a/drivers/net/macvtap.c
+++ b/drivers/net/macvtap.c
@@ -68,6 +68,8 @@ static const struct proto_ops macvtap_socket_ops;
 #define TUN_OFFLOADS (NETIF_F_HW_CSUM | NETIF_F_TSO_ECN | NETIF_F_TSO | \
                      NETIF_F_TSO6 | NETIF_F_UFO)
 #define RX_OFFLOADS (NETIF_F_GRO | NETIF_F_LRO)
+#define TAP_FEATURES (NETIF_F_GSO | NETIF_F_SG)
+
 /*
  * RCU usage:
  * The macvtap_queue and the macvlan_dev are loosely coupled, the
@@ -278,7 +280,8 @@ static int macvtap_forward(struct net_device *dev, struct sk_buff *skb)
 {
        struct macvlan_dev *vlan = netdev_priv(dev);
        struct macvtap_queue *q = macvtap_get_queue(dev, skb);
-       netdev_features_t features;
+       netdev_features_t features = TAP_FEATURES;
+
        if (!q)
                goto drop;
 
@@ -287,9 +290,11 @@ static int macvtap_forward(struct net_device *dev, struct sk_buff *skb)
 
        skb->dev = dev;
        /* Apply the forward feature mask so that we perform segmentation
-        * according to users wishes.
+        * according to users wishes.  This only works if VNET_HDR is
+        * enabled.
         */
-       features = netif_skb_features(skb) & vlan->tap_features;
+       if (q->flags & IFF_VNET_HDR)
+               features |= vlan->tap_features;
        if (netif_needs_gso(skb, features)) {
                struct sk_buff *segs = __skb_gso_segment(skb, features, false);
 
@@ -1064,8 +1069,7 @@ static int set_offload(struct macvtap_queue *q, unsigned long arg)
        /* tap_features are the same as features on tun/tap and
         * reflect user expectations.
         */
-       vlan->tap_features = vlan->dev->features &
-                           (feature_mask | ~TUN_OFFLOADS);
+       vlan->tap_features = feature_mask;
        vlan->set_features = features;
        netdev_update_features(vlan->dev);
 
@@ -1161,10 +1165,6 @@ static long macvtap_ioctl(struct file *file, unsigned int cmd,
                            TUN_F_TSO_ECN | TUN_F_UFO))
                        return -EINVAL;
 
-               /* TODO: only accept frames with the features that
-                        got enabled for forwarded frames */
-               if (!(q->flags & IFF_VNET_HDR))
-                       return  -EINVAL;
                rtnl_lock();
                ret = set_offload(q, arg);
                rtnl_unlock();