diff options
authorOussama Ghorbel <ou.ghorbel@gmail.com>2013-10-07 18:50:05 +0100
committerDavid S. Miller <davem@davemloft.net>2013-10-08 16:32:40 -0400
commit0e719e3a53cc03bc1bafbb2cae1ddf99a0d73ab0 (patch)
parentxen-netback: transition to CLOSED when removing a VIF (diff)
ipv6: Fix the upper MTU limit in GRE tunnel
Unlike ipv4, the struct member hlen holds the length of the GRE and ipv6 headers. This length is also counted in dev->hard_header_len. Perhaps, it's more clean to modify the hlen to count only the GRE header without ipv6 header as the variable name suggest, but the simple way to fix this without regression risk is simply modify the calculation of the limit in ip6gre_tunnel_change_mtu function. Verified in kernel version v3.11. Signed-off-by: Oussama Ghorbel <ou.ghorbel@gmail.com> Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net>
1 files changed, 1 insertions, 2 deletions
diff --git a/net/ipv6/ip6_gre.c b/net/ipv6/ip6_gre.c
index 7bb5446b9d73..1ef1fa2b22a6 100644
--- a/net/ipv6/ip6_gre.c
+++ b/net/ipv6/ip6_gre.c
@@ -1173,9 +1173,8 @@ done:
static int ip6gre_tunnel_change_mtu(struct net_device *dev, int new_mtu)
- struct ip6_tnl *tunnel = netdev_priv(dev);
if (new_mtu < 68 ||
- new_mtu > 0xFFF8 - dev->hard_header_len - tunnel->hlen)
+ new_mtu > 0xFFF8 - dev->hard_header_len)
return -EINVAL;
dev->mtu = new_mtu;
return 0;