Currently pskb_trim_rcsum() is always done on the RX path. However, IPv6 jumbo packets hide the real packet len in the Hop-by-hop option header, which should be parsed before doing the trim. In ip6_rcv_core() it calls ipv6_parse_hopopts() to handle the Hop-by-hop option header then do pskb_trim_rcsum(). The similar process should also be done properly before pskb_trim_rcsum() on the RX path of bridge and openvswitch and tc. This patchset improves the function handling the Hop-by-hop option header in bridge, and moves this function into netfilter utils, and then uses it in nf_conntrack_ovs for openvswitch and tc conntrack. Note that this patch is especially needed after the IPv6 BIG TCP was supported in kernel, which is using IPv6 Jumbo packets, and the last patch adds a big tcp selftest, which also covers it. Xin Long (6): netfilter: bridge: call pskb_may_pull in br_nf_check_hbh_len netfilter: bridge: check len before accessing more nh data netfilter: bridge: move pskb_trim_rcsum out of br_nf_check_hbh_len netfilter: move br_nf_check_hbh_len to utils netfilter: use nf_ip6_check_hbh_len in nf_ct_skb_network_trim selftests: add a selftest for big tcp include/linux/netfilter_ipv6.h | 2 + net/bridge/br_netfilter_ipv6.c | 79 ++--------- net/netfilter/nf_conntrack_ovs.c | 11 +- net/netfilter/utils.c | 54 ++++++++ tools/testing/selftests/net/Makefile | 1 + tools/testing/selftests/net/big_tcp.sh | 180 +++++++++++++++++++++++++ 6 files changed, 256 insertions(+), 71 deletions(-) create mode 100755 tools/testing/selftests/net/big_tcp.sh -- 2.39.1
