tunneling: Force selection of an IP ID with GRE.

[sliver-openvswitch.git] / datapath / vport-gre.c

diff --git a/datapath/vport-gre.c b/datapath/vport-gre.c
index 9c1c1cc..46e0be8 100644 (file)
--- a/datapath/vport-gre.c
+++ b/datapath/vport-gre.c
@@ -103,9 +103,12 @@ static struct sk_buff *gre_update_header(const struct vport *vport,
                                                0));
        /*
         * Allow our local IP stack to fragment the outer packet even if the
-        * DF bit is set as a last resort.
+        * DF bit is set as a last resort.  We also need to force selection of
+        * an IP ID here because Linux will otherwise leave it at 0 if the
+        * packet originally had DF set.
         */
        skb->local_df = 1;
+       __ip_select_ident(ip_hdr(skb), dst, 0);
 
        return skb;
 }