This is a note to let you know that I've just added the patch titled gso: fix payload length when gso_size is zero to the 4.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: gso-fix-payload-length-when-gso_size-is-zero.patch and it can be found in the queue-4.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Wed Nov 15 17:25:34 CET 2017 From: Alexey Kodanev <alexey.kodanev@xxxxxxxxxx> Date: Fri, 6 Oct 2017 19:02:35 +0300 Subject: gso: fix payload length when gso_size is zero From: Alexey Kodanev <alexey.kodanev@xxxxxxxxxx> [ Upstream commit 3d0241d57c7b25bb75ac9d7a62753642264fdbce ] 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.kodanev@xxxxxxxxxx> Acked-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- 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(-) --- a/net/ipv4/gre_offload.c +++ b/net/ipv4/gre_offload.c @@ -98,7 +98,7 @@ static struct sk_buff *gre_gso_segment(s 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 --- a/net/ipv4/udp_offload.c +++ b/net/ipv4/udp_offload.c @@ -122,7 +122,7 @@ static struct sk_buff *__skb_udp_tunnel_ * 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); --- a/net/ipv6/ip6_offload.c +++ b/net/ipv6/ip6_offload.c @@ -105,7 +105,7 @@ static struct sk_buff *ipv6_gso_segment( 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); Patches currently in stable-queue which might be from alexey.kodanev@xxxxxxxxxx are queue-4.13/gso-fix-payload-length-when-gso_size-is-zero.patch