wireguard: send: account for mtu=0 devices

[linux-2.6-microblaze.git] / drivers / net / wireguard / device.c

diff --git a/drivers/net/wireguard/device.c b/drivers/net/wireguard/device.c
index 43db442..cdc9696 100644 (file)
--- a/drivers/net/wireguard/device.c
+++ b/drivers/net/wireguard/device.c
@@ -258,6 +258,8 @@ static void wg_setup(struct net_device *dev)
        enum { WG_NETDEV_FEATURES = NETIF_F_HW_CSUM | NETIF_F_RXCSUM |
                                    NETIF_F_SG | NETIF_F_GSO |
                                    NETIF_F_GSO_SOFTWARE | NETIF_F_HIGHDMA };
+       const int overhead = MESSAGE_MINIMUM_LENGTH + sizeof(struct udphdr) +
+                            max(sizeof(struct ipv6hdr), sizeof(struct iphdr));
 
        dev->netdev_ops = &netdev_ops;
        dev->hard_header_len = 0;
@@ -271,9 +273,8 @@ static void wg_setup(struct net_device *dev)
        dev->features |= WG_NETDEV_FEATURES;
        dev->hw_features |= WG_NETDEV_FEATURES;
        dev->hw_enc_features |= WG_NETDEV_FEATURES;
-       dev->mtu = ETH_DATA_LEN - MESSAGE_MINIMUM_LENGTH -
-                  sizeof(struct udphdr) -
-                  max(sizeof(struct ipv6hdr), sizeof(struct iphdr));
+       dev->mtu = ETH_DATA_LEN - overhead;
+       dev->max_mtu = round_down(INT_MAX, MESSAGE_PADDING_MULTIPLE) - overhead;
 
        SET_NETDEV_DEVTYPE(dev, &device_type);