When gso_size reset to zero for the tail segment in skb_segment(), later in ipv6_gso_segment(), __skb_udp_tunnel_segment() and gre_gso_segment() we will get incorrect results (payload length, pcsum) for that segment. inet_gso_segment() already has a check for gso_size before calculating payload.
The issue was found with LTP vxlan & gre tests over ixgbe NIC. Fixes: 07b26c9454a2 ("gso: Support partial splitting at the frag_list pointer") Signed-off-by: Alexey Kodanev <alexey.koda...@oracle.com> --- v2: also added skb_is_gso to gre_gso_segment() and __skb_udp_tunnel_segment() net/ipv4/gre_offload.c | 2 +- net/ipv4/udp_offload.c | 2 +- net/ipv6/ip6_offload.c | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c index d5cac99..8c72034 100644 --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -98,7 +98,7 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb, greh = (struct gre_base_hdr *)skb_transport_header(skb); pcsum = (__sum16 *)(greh + 1); - if (gso_partial) { + if (gso_partial && skb_is_gso(skb)) { unsigned int partial_adj; /* Adjust checksum to account for the fact that diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c index 0932c85..6401574 100644 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -122,7 +122,7 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb, * will be using a length value equal to only one MSS sized * segment instead of the entire frame. */ - if (gso_partial) { + if (gso_partial && skb_is_gso(skb)) { uh->len = htons(skb_shinfo(skb)->gso_size + SKB_GSO_CB(skb)->data_offset + skb->head - (unsigned char *)uh); diff --git a/net/ipv6/ip6_offload.c b/net/ipv6/ip6_offload.c index cdb3728..4a87f94 100644 --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -105,7 +105,7 @@ static struct sk_buff *ipv6_gso_segment(struct sk_buff *skb, for (skb = segs; skb; skb = skb->next) { ipv6h = (struct ipv6hdr *)(skb_mac_header(skb) + nhoff); - if (gso_partial) + if (gso_partial && skb_is_gso(skb)) payload_len = skb_shinfo(skb)->gso_size + SKB_GSO_CB(skb)->data_offset + skb->head - (unsigned char *)(ipv6h + 1); -- 1.8.3.1