For some protocol's gso, like SCTP, it's using GSO_BY_FRAGS for gso_size. When using UDP to encapsulate its packet, it will return error in udp6_ufo_fragment() as skb->len < gso_size, and it will never go to the gso tunnel processing. So we should move this check after udp gso tunnel processing, the same as udp4_ufo_fragment() does. While at it, also tidy the variables up. Signed-off-by: Xin Long <lucien.xin@xxxxxxxxx> --- net/ipv6/udp_offload.c | 154 ++++++++++++++++++++++++------------------------- 1 file changed, 76 insertions(+), 78 deletions(-) diff --git a/net/ipv6/udp_offload.c b/net/ipv6/udp_offload.c index 584157a..3c5ec8e 100644 --- a/net/ipv6/udp_offload.c +++ b/net/ipv6/udp_offload.c @@ -17,96 +17,94 @@ static struct sk_buff *udp6_ufo_fragment(struct sk_buff *skb, netdev_features_t features) { + u8 nexthdr, frag_hdr_sz = sizeof(struct frag_hdr); + unsigned int unfrag_ip6hlen, unfrag_len, mss; struct sk_buff *segs = ERR_PTR(-EINVAL); - unsigned int mss; - unsigned int unfrag_ip6hlen, unfrag_len; - struct frag_hdr *fptr; + const struct ipv6hdr *ipv6h; u8 *packet_start, *prevhdr; - u8 nexthdr; - u8 frag_hdr_sz = sizeof(struct frag_hdr); + struct frag_hdr *fptr; + int tnl_hlen, err; + struct udphdr *uh; __wsum csum; - int tnl_hlen; - int err; - mss = skb_shinfo(skb)->gso_size; - if (unlikely(skb->len <= mss)) + if (skb->encapsulation && + (skb_shinfo(skb)->gso_type & + (SKB_GSO_UDP_TUNNEL | SKB_GSO_UDP_TUNNEL_CSUM))) { + segs = skb_udp_tunnel_segment(skb, features, true); goto out; + } - if (skb->encapsulation && skb_shinfo(skb)->gso_type & - (SKB_GSO_UDP_TUNNEL|SKB_GSO_UDP_TUNNEL_CSUM)) - segs = skb_udp_tunnel_segment(skb, features, true); - else { - const struct ipv6hdr *ipv6h; - struct udphdr *uh; + if (!(skb_shinfo(skb)->gso_type & (SKB_GSO_UDP | SKB_GSO_UDP_L4))) + goto out; - if (!(skb_shinfo(skb)->gso_type & (SKB_GSO_UDP | SKB_GSO_UDP_L4))) - goto out; + if (!pskb_may_pull(skb, sizeof(struct udphdr))) + goto out; - if (!pskb_may_pull(skb, sizeof(struct udphdr))) - goto out; + if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) + return __udp_gso_segment(skb, features); - if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) - return __udp_gso_segment(skb, features); - - /* Do software UFO. Complete and fill in the UDP checksum as HW cannot - * do checksum of UDP packets sent as multiple IP fragments. - */ - - uh = udp_hdr(skb); - ipv6h = ipv6_hdr(skb); - - uh->check = 0; - csum = skb_checksum(skb, 0, skb->len, 0); - uh->check = udp_v6_check(skb->len, &ipv6h->saddr, - &ipv6h->daddr, csum); - if (uh->check == 0) - uh->check = CSUM_MANGLED_0; - - skb->ip_summed = CHECKSUM_UNNECESSARY; - - /* If there is no outer header we can fake a checksum offload - * due to the fact that we have already done the checksum in - * software prior to segmenting the frame. - */ - if (!skb->encap_hdr_csum) - features |= NETIF_F_HW_CSUM; - - /* Check if there is enough headroom to insert fragment header. */ - tnl_hlen = skb_tnl_header_len(skb); - if (skb->mac_header < (tnl_hlen + frag_hdr_sz)) { - if (gso_pskb_expand_head(skb, tnl_hlen + frag_hdr_sz)) - goto out; - } + mss = skb_shinfo(skb)->gso_size; + if (unlikely(skb->len <= mss)) + goto out; - /* Find the unfragmentable header and shift it left by frag_hdr_sz - * bytes to insert fragment header. - */ - err = ip6_find_1stfragopt(skb, &prevhdr); - if (err < 0) - return ERR_PTR(err); - unfrag_ip6hlen = err; - nexthdr = *prevhdr; - *prevhdr = NEXTHDR_FRAGMENT; - unfrag_len = (skb_network_header(skb) - skb_mac_header(skb)) + - unfrag_ip6hlen + tnl_hlen; - packet_start = (u8 *) skb->head + SKB_GSO_CB(skb)->mac_offset; - memmove(packet_start-frag_hdr_sz, packet_start, unfrag_len); - - SKB_GSO_CB(skb)->mac_offset -= frag_hdr_sz; - skb->mac_header -= frag_hdr_sz; - skb->network_header -= frag_hdr_sz; - - fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen); - fptr->nexthdr = nexthdr; - fptr->reserved = 0; - fptr->identification = ipv6_proxy_select_ident(dev_net(skb->dev), skb); - - /* Fragment the skb. ipv6 header and the remaining fields of the - * fragment header are updated in ipv6_gso_segment() - */ - segs = skb_segment(skb, features); + /* Do software UFO. Complete and fill in the UDP checksum as HW cannot + * do checksum of UDP packets sent as multiple IP fragments. + */ + + uh = udp_hdr(skb); + ipv6h = ipv6_hdr(skb); + + uh->check = 0; + csum = skb_checksum(skb, 0, skb->len, 0); + uh->check = udp_v6_check(skb->len, &ipv6h->saddr, + &ipv6h->daddr, csum); + if (uh->check == 0) + uh->check = CSUM_MANGLED_0; + + skb->ip_summed = CHECKSUM_UNNECESSARY; + + /* If there is no outer header we can fake a checksum offload + * due to the fact that we have already done the checksum in + * software prior to segmenting the frame. + */ + if (!skb->encap_hdr_csum) + features |= NETIF_F_HW_CSUM; + + /* Check if there is enough headroom to insert fragment header. */ + tnl_hlen = skb_tnl_header_len(skb); + if (skb->mac_header < (tnl_hlen + frag_hdr_sz)) { + if (gso_pskb_expand_head(skb, tnl_hlen + frag_hdr_sz)) + goto out; } + /* Find the unfragmentable header and shift it left by frag_hdr_sz + * bytes to insert fragment header. + */ + err = ip6_find_1stfragopt(skb, &prevhdr); + if (err < 0) + return ERR_PTR(err); + unfrag_ip6hlen = err; + nexthdr = *prevhdr; + *prevhdr = NEXTHDR_FRAGMENT; + unfrag_len = (skb_network_header(skb) - skb_mac_header(skb)) + + unfrag_ip6hlen + tnl_hlen; + packet_start = (u8 *)skb->head + SKB_GSO_CB(skb)->mac_offset; + memmove(packet_start - frag_hdr_sz, packet_start, unfrag_len); + + SKB_GSO_CB(skb)->mac_offset -= frag_hdr_sz; + skb->mac_header -= frag_hdr_sz; + skb->network_header -= frag_hdr_sz; + + fptr = (struct frag_hdr *)(skb_network_header(skb) + unfrag_ip6hlen); + fptr->nexthdr = nexthdr; + fptr->reserved = 0; + fptr->identification = ipv6_proxy_select_ident(dev_net(skb->dev), skb); + + /* Fragment the skb. ipv6 header and the remaining fields of the + * fragment header are updated in ipv6_gso_segment() + */ + segs = skb_segment(skb, features); + out: return segs; } -- 2.1.0