1 files changed, 10 insertions, 2 deletions

diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index a791552e0422..583b77e2f69b 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1430,9 +1430,17 @@ ip6_tnl_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 static int
 ip6_tnl_change_mtu(struct net_device *dev, int new_mtu)
 {
-        if (new_mtu < IPV6_MIN_MTU) {
-                return -EINVAL;
+        struct ip6_tnl *tnl = netdev_priv(dev);
+
+        if (tnl->parms.proto == IPPROTO_IPIP) {
+                if (new_mtu < 68)
+                        return -EINVAL;
+        } else {
+                if (new_mtu < IPV6_MIN_MTU)
+                        return -EINVAL;
         }
+        if (new_mtu > 0xFFF8 - dev->hard_header_len)
+                return -EINVAL;
         dev->mtu = new_mtu;
         return 0;
 }