bridge: correct IPv6 checksum after pull

Bridge multicast snooping of ICMPv6 would incorrectly report a checksum problem
when used with Ethernet devices like sky2 that use CHECKSUM_COMPLETE.
When bytes are removed from skb, the computed checksum needs to be adjusted.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Tested-by: Martin Volf <martin.volf.42@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 2eefe275b338..a5f4e5769809 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c
@@ -1501,6 +1501,8 @@ static int br_multicast_ipv6_rcv(struct net_bridge *br,
 
         __skb_pull(skb2, offset);
         skb_reset_transport_header(skb2);
+        skb_postpull_rcsum(skb2, skb_network_header(skb2),
+                           skb_network_header_len(skb2));
 
         icmp6_type = icmp6_hdr(skb2)->icmp6_type;