datapath: openvswitch: update checksum in {push,pop}_mpls

Upstream commit:
    commit bc7cc5999fd392cc799630d7e375b2f4e29cc398
    Author: Simon Horman <simon.horman@netronome.com>

    openvswitch: update checksum in {push,pop}_mpls

    In the case of CHECKSUM_COMPLETE the skb checksum should be updated in
    {push,pop}_mpls() as they the type in the ethernet header.

    As suggested by Pravin Shelar.

    Cc: Pravin Shelar <pshelar@ovn.org>
    Fixes: 25cd9ba0abc0 ("openvswitch: Add basic MPLS support to kernel")
    Signed-off-by: Simon Horman <simon.horman@netronome.com>
    Acked-by: Pravin B Shelar <pshelar@ovn.org>
    Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Pravin B Shelar <pshelar@ovn.org>
Acked-by: Jesse Gross <jesse@kernel.org>

diff --git a/datapath/actions.c b/datapath/actions.c
index fb5fa8a..abf7e3b 100644 (file)
--- a/datapath/actions.c
+++ b/datapath/actions.c
@@ -139,11 +139,23 @@ static bool is_flow_key_valid(const struct sw_flow_key *key)
        return !!key->eth.type;
 }
 
+static void update_ethertype(struct sk_buff *skb, struct ethhdr *hdr,
+                            __be16 ethertype)
+{
+       if (skb->ip_summed == CHECKSUM_COMPLETE) {
+               __be16 diff[] = { ~(hdr->h_proto), ethertype };
+
+               skb->csum = ~csum_partial((char *)diff, sizeof(diff),
+                                       ~skb->csum);
+       }
+
+       hdr->h_proto = ethertype;
+}
+
 static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
                     const struct ovs_action_push_mpls *mpls)
 {
        __be32 *new_mpls_lse;
-       struct ethhdr *hdr;
 
        /* Networking stack do not allow simultaneous Tunnel and MPLS GSO. */
        if (skb->encapsulation)
@@ -162,8 +174,7 @@ static int push_mpls(struct sk_buff *skb, struct sw_flow_key *key,
 
        skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
 
-       hdr = eth_hdr(skb);
-       hdr->h_proto = mpls->mpls_ethertype;
+       update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
        if (!ovs_skb_get_inner_protocol(skb))
                ovs_skb_set_inner_protocol(skb, skb->protocol);
        skb->protocol = mpls->mpls_ethertype;
@@ -194,7 +205,7 @@ static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
         * field correctly in the presence of VLAN tags.
         */
        hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN);
-       hdr->h_proto = ethertype;
+       update_ethertype(skb, hdr, ethertype);
        if (eth_p_mpls(skb->protocol))
                skb->protocol = ethertype;