diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 2578aa7f9ff9..29651b1a0bc7 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -590,9 +590,12 @@ struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb, uh = udp_hdr(seg); } - /* last packet can be partial gso_size, account for that in checksum */ - newlen = htons(skb_tail_pointer(seg) - skb_transport_header(seg) + - seg->data_len); + /* Unless skb fits perfectly as GSO_PARTIAL, the trailing + * segment may not be full MSS, account for that in the checksum + */ + if (!skb_is_gso(seg)) + newlen = htons(skb_tail_pointer(seg) - + skb_transport_header(seg) + seg->data_len); check = csum16_add(csum16_sub(uh->check, uh->len), newlen); uh->len = newlen;