The commit a2fb4bc4e2a6a03 ("net: implement virtio helpers to handle UDP GSO tunneling.") introduces support for the UDP GSO tunnel feature in virtio-net. The virtio spec says: If the \field{gso_type} has the VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV4 bit or VIRTIO_NET_HDR_GSO_UDP_TUNNEL_IPV6 bit set, \field{hdr_len} accounts for all the headers up to and including the inner transport. The commit did not update the hdr_len to include the inner transport. I observed that the "hdr_len" is 116 for this packet: 17:36:18.241105 52:55:00:d1:27:0a > 2e:2c:df:46:a9:e1, ethertype IPv4 (0x0800), length 2912: (tos 0x0, ttl 64, id 45197, offset 0, flags [none], proto UDP (17), length 2898) 192.168.122.100.50613 > 192.168.122.1.4789: [bad udp cksum 0x8106 -> 0x26a0!] VXLAN, flags [I] (0x08), vni 1 fa:c3:ba:82:05:ee > ce:85:0c:31:77:e5, ethertype IPv4 (0x0800), length 2862: (tos 0x0, ttl 64, id 14678, offset 0, flags [DF], proto TCP (6), length 2848) 192.168.3.1.49880 > 192.168.3.2.9898: Flags [P.], cksum 0x9266 (incorrect -> 0xaa20), seq 515667:518463, ack 1, win 64, options [nop,nop,TS val 2990048824 ecr 2798801412], length 2796 116 = 14(mac) + 20(ip) + 8(udp) + 8(vxlan) + 14(inner mac) + 20(inner ip) + 32(innner tcp) Fixes: a2fb4bc4e2a6a03 ("net: implement virtio helpers to handle UDP GSO tunneling.") Signed-off-by: Xuan Zhuo --- include/linux/virtio_net.h | 35 ++++++++++++++++++++++++----------- 1 file changed, 24 insertions(+), 11 deletions(-) diff --git a/include/linux/virtio_net.h b/include/linux/virtio_net.h index 6ef0b737d548..46b04816d333 100644 --- a/include/linux/virtio_net.h +++ b/include/linux/virtio_net.h @@ -207,6 +207,14 @@ static inline int virtio_net_hdr_to_skb(struct sk_buff *skb, return __virtio_net_hdr_to_skb(skb, hdr, little_endian, hdr->gso_type); } +static inline int virtio_net_tcp_hdrlen(const struct sk_buff *skb, bool tnl) +{ + if (tnl) + return inner_tcp_hdrlen(skb); + + return tcp_hdrlen(skb); +} + static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb, struct virtio_net_hdr *hdr, bool little_endian, @@ -217,25 +225,33 @@ static inline int virtio_net_hdr_from_skb(const struct sk_buff *skb, if (skb_is_gso(skb)) { struct skb_shared_info *sinfo = skb_shinfo(skb); + bool tnl = false; u16 hdr_len = 0; - /* In certain code paths (such as the af_packet.c receive path), - * this function may be called without a transport header. - * In this case, we do not need to set the hdr_len. - */ - if (skb_transport_header_was_set(skb)) - hdr_len = skb_transport_offset(skb); + if (sinfo->gso_type & (SKB_GSO_UDP_TUNNEL | + SKB_GSO_UDP_TUNNEL_CSUM)) { + tnl = true; + hdr_len = skb_inner_transport_offset(skb); + + } else { + /* In certain code paths (such as the af_packet.c receive path), + * this function may be called without a transport header. + * In this case, we do not need to set the hdr_len. + */ + if (skb_transport_header_was_set(skb)) + hdr_len = skb_transport_offset(skb); + } hdr->gso_size = __cpu_to_virtio16(little_endian, sinfo->gso_size); if (sinfo->gso_type & SKB_GSO_TCPV4) { hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4; if (hdr_len) - hdr_len += tcp_hdrlen(skb); + hdr_len += virtio_net_tcp_hdrlen(skb, tnl); } else if (sinfo->gso_type & SKB_GSO_TCPV6) { hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6; if (hdr_len) - hdr_len += tcp_hdrlen(skb); + hdr_len += virtio_net_tcp_hdrlen(skb, tnl); } else if (sinfo->gso_type & SKB_GSO_UDP_L4) { hdr->gso_type = VIRTIO_NET_HDR_GSO_UDP_L4; if (hdr_len) @@ -420,10 +436,7 @@ virtio_net_hdr_tnl_from_skb(const struct sk_buff *skb, vhdr->hash_hdr.hash_report = 0; vhdr->hash_hdr.padding = 0; - /* Let the basic parsing deal with plain GSO features. */ - skb_shinfo(skb)->gso_type &= ~tnl_gso_type; ret = virtio_net_hdr_from_skb(skb, hdr, true, false, vlan_hlen); - skb_shinfo(skb)->gso_type |= tnl_gso_type; if (ret) return ret; -- 2.32.0.3.g01195cf9f