Patch "gso: fix payload length when gso_size is zero" has been added to the 4.13-stable tree

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 <[email protected]> know about it.

From: Alexey Kodanev <[email protected]>
Date: Fri, 6 Oct 2017 19:02:35 +0300
Subject: gso: fix payload length when gso_size is zero

From: Alexey Kodanev <[email protected]>

[ 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.

---
 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(-)

@@ -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

@@ -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);

@@ -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 [email protected] are

queue-4.13/gso-fix-payload-length-when-gso_size-is-zero.patch