geneve: fix max_mtu setting
For ipv6+udp+geneve encapsulation data, the max_mtu should subtract
sizeof(ipv6hdr), instead of sizeof(iphdr).
Signed-off-by: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index cc39cef..9b3dc3c 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1072,12 +1072,17 @@
static int __geneve_change_mtu(struct net_device *dev, int new_mtu, bool strict)
{
+ struct geneve_dev *geneve = netdev_priv(dev);
/* The max_mtu calculation does not take account of GENEVE
* options, to avoid excluding potentially valid
* configurations.
*/
- int max_mtu = IP_MAX_MTU - GENEVE_BASE_HLEN - sizeof(struct iphdr)
- - dev->hard_header_len;
+ int max_mtu = IP_MAX_MTU - GENEVE_BASE_HLEN - dev->hard_header_len;
+
+ if (geneve->remote.sa.sa_family == AF_INET6)
+ max_mtu -= sizeof(struct ipv6hdr);
+ else
+ max_mtu -= sizeof(struct iphdr);
if (new_mtu < 68)
return -EINVAL;