ip6_tunnel: remove magic mtu value 0xFFF8
I don't know where this value comes from (probably a copy and paste and
paste and paste ...).
Let's use standard values which are a bit greater.
Link: https://git.kernel.org/pub/scm/linux/kernel/git/davem/netdev-vger-cvs.git/commit/?id=e5afd356a411a
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index da66aaa..00e138a 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -1692,8 +1692,13 @@
if (new_mtu < ETH_MIN_MTU)
return -EINVAL;
}
- if (new_mtu > 0xFFF8 - dev->hard_header_len)
- return -EINVAL;
+ if (tnl->parms.proto == IPPROTO_IPV6 || tnl->parms.proto == 0) {
+ if (new_mtu > IP6_MAX_MTU - dev->hard_header_len)
+ return -EINVAL;
+ } else {
+ if (new_mtu > IP_MAX_MTU - dev->hard_header_len)
+ return -EINVAL;
+ }
dev->mtu = new_mtu;
return 0;
}
@@ -1841,7 +1846,7 @@
if (!(t->parms.flags & IP6_TNL_F_IGN_ENCAP_LIMIT))
dev->mtu -= 8;
dev->min_mtu = ETH_MIN_MTU;
- dev->max_mtu = 0xFFF8 - dev->hard_header_len;
+ dev->max_mtu = IP6_MAX_MTU - dev->hard_header_len;
return 0;