Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost

[linux-2.6-microblaze.git] / net / dsa / tag_hellcreek.c

diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
index f64b805..eb204ad 100644 (file)
--- a/net/dsa/tag_hellcreek.c
+++ b/net/dsa/tag_hellcreek.c
@@ -21,6 +21,14 @@ static struct sk_buff *hellcreek_xmit(struct sk_buff *skb,
        struct dsa_port *dp = dsa_slave_to_port(dev);
        u8 *tag;
 
+       /* Calculate checksums (if required) before adding the trailer tag to
+        * avoid including it in calculations. That would lead to wrong
+        * checksums after the switch strips the tag.
+        */
+       if (skb->ip_summed == CHECKSUM_PARTIAL &&
+           skb_checksum_help(skb))
+               return NULL;
+
        /* Tag encoding */
        tag  = skb_put(skb, HELLCREEK_TAG_LEN);
        *tag = BIT(dp->index);