Merge tag 'please-pull-misc-4.7' of git://git.kernel.org/pub/scm/linux/kernel/git...

[deliverable/linux.git] / net / ipv4 / gre_offload.c

diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index 6a5bd43178666eed954c4ee6f22837059fad470d..e88190a8699ad9c900be71d80d8ff3f9e12471ff 100644 (file)
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -32,10 +32,12 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
                                  SKB_GSO_UDP |
                                  SKB_GSO_DODGY |
                                  SKB_GSO_TCP_ECN |
+                                 SKB_GSO_TCP_FIXEDID |
                                  SKB_GSO_GRE |
                                  SKB_GSO_GRE_CSUM |
                                  SKB_GSO_IPIP |
-                                 SKB_GSO_SIT)))
+                                 SKB_GSO_SIT |
+                                 SKB_GSO_PARTIAL)))
                goto out;
 
        if (!skb->encapsulation)
@@ -86,7 +88,7 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
        skb = segs;
        do {
                struct gre_base_hdr *greh;
-               __be32 *pcsum;
+               __sum16 *pcsum;
 
                /* Set up inner headers if we are offloading inner checksum */
                if (skb->ip_summed == CHECKSUM_PARTIAL) {
@@ -106,10 +108,25 @@ static struct sk_buff *gre_gso_segment(struct sk_buff *skb,
                        continue;
 
                greh = (struct gre_base_hdr *)skb_transport_header(skb);
-               pcsum = (__be32 *)(greh + 1);
+               pcsum = (__sum16 *)(greh + 1);
+
+               if (skb_is_gso(skb)) {
+                       unsigned int partial_adj;
+
+                       /* Adjust checksum to account for the fact that
+                        * the partial checksum is based on actual size
+                        * whereas headers should be based on MSS size.
+                        */
+                       partial_adj = skb->len + skb_headroom(skb) -
+                                     SKB_GSO_CB(skb)->data_offset -
+                                     skb_shinfo(skb)->gso_size;
+                       *pcsum = ~csum_fold((__force __wsum)htonl(partial_adj));
+               } else {
+                       *pcsum = 0;
+               }
 
-               *pcsum = 0;
-               *(__sum16 *)pcsum = gso_make_checksum(skb, 0);
+               *(pcsum + 1) = 0;
+               *pcsum = gso_make_checksum(skb, 0);
        } while ((skb = skb->next));
 out:
        return segs;
@@ -275,6 +292,18 @@ static const struct net_offload gre_offload = {
 
 static int __init gre_offload_init(void)
 {
-       return inet_add_offload(&gre_offload, IPPROTO_GRE);
+       int err;
+
+       err = inet_add_offload(&gre_offload, IPPROTO_GRE);
+#if IS_ENABLED(CONFIG_IPV6)
+       if (err)
+               return err;
+
+       err = inet6_add_offload(&gre_offload, IPPROTO_GRE);
+       if (err)
+               inet_del_offload(&gre_offload, IPPROTO_GRE);
+#endif
+
+       return err;
 }
 device_initcall(gre_offload_init);