IPv6:
[ 2460.557303] +++ br_multicast_ipv6_rcv()
[ 2460.558114] +++ br_multicast_ipv6_rcv() here 0.5
[ 2460.558114] +++ br_multicast_ipv6_rcv() len: 36, offset: 48, skb_network_offset(skb2): 0
[ 2460.558114] +++ br_multicast_ipv6_rcv() new len: -12
[ 2460.558114] +++ br_multicast_ipv6_rcv() skb2->len: 28 len: -12 skb->len: 76
[ 2460.558114] +++ br_multicast_ipv6_rcv() here 1.5
[ 2460.558114] +++ br_multicast_ipv6_rcv() here 1.7, skb2->csum is 0
[ 2460.558114] +++ br_multicast_ipv6_rcv() here 1.8, skb_checksum_complete(skb2): 81e9 (skb): 2e60
[ 2464.981808] +++ br_multicast_ipv6_rcv()
[ 2464.982388] +++ br_multicast_ipv6_rcv() here 0.5
[ 2465.062634] +++ br_multicast_ipv6_rcv() len: 36, offset: 48, skb_network_offset(skb2): 0
[ 2465.066698] +++ br_multicast_ipv6_rcv() new len: -12
[ 2465.069183] +++ br_multicast_ipv6_rcv() skb2->len: 28 len: -12 skb->len: 76
[ 2465.072013] +++ br_multicast_ipv6_rcv() here 1.5
[ 2465.074217] +++ br_multicast_ipv6_rcv() here 1.7, skb2->csum is 0
[ 2465.076785] +++ br_multicast_ipv6_rcv() here 1.8, skb_checksum_complete(skb2): 81e9 (skb): 2e60

IPv4:
[ 2325.265830] +++ br_multicast_ipv4_rcv() skb2->len: 40 len: 40 skb->len: 40
[ 2325.266567] +++ br_multicast_ipv4_rcv() 2) skb2->len: 16 len: 16 skb->len: 16
[ 2325.266567] +++ br_multicast_ipv4_rcv() here 1.7, skb2->csum is 0
[ 2325.266567] +++ br_multicast_ipv4_rcv() here 1.8, skb_checksum_complete: 0
[ 2325.266567] +++ br_ip4_multicast_add_group() eth1 224.0.1.123
[ 2327.326179] +++ br_multicast_ipv4_rcv() skb2->len: 40 len: 40 skb->len: 40
[ 2327.326674] +++ br_multicast_ipv4_rcv() 2) skb2->len: 16 len: 16 skb->len: 16
[ 2327.326674] +++ br_multicast_ipv4_rcv() here 1.7, skb2->csum is 0
[ 2327.326674] +++ br_multicast_ipv4_rcv() here 1.8, skb_checksum_complete: 0
[ 2327.326674] +++ br_ip4_multicast_add_group() eth1 224.0.1.123