From: Haishuang Yan <yanhaishuang@cmss.chinamobile.com>
Date: Sat, 2 Jul 2016 07:02:48 +0000 (+0800)
Subject: geneve: fix max_mtu setting
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=d5d5e8d55732c7c35c354e45e3b0af2795978a57;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git

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 cc39cefeae45..9b3dc3c61e00 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -1072,12 +1072,17 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev)
 
 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;