On Wed, Jun 1, 2016 at 11:24 PM, Simon Horman
<simon.hor...@netronome.com> wrote:
> Allow push and pop mpls actions to act on layer 3 packets by teaching
> them not to access non-existent L2 headers of such packets.
>
> Signed-off-by: Simon Horman <simon.hor...@netronome.com>
> ---
> v10
> * Limit scope of hdr in {push,pop}_mpls()
>
> v9
> * New Patch
> ---
> net/openvswitch/actions.c | 19 ++++++++++++-------
> 1 file changed, 12 insertions(+), 7 deletions(-)
>
> diff --git a/net/openvswitch/actions.c b/net/openvswitch/actions.c
> index 9a3eb7a0ebf4..15f130e4c22b 100644
> --- a/net/openvswitch/actions.c
> +++ b/net/openvswitch/actions.c
> @@ -172,7 +172,8 @@ static int push_mpls(struct sk_buff *skb, struct
> sw_flow_key *key,
>
> skb_postpush_rcsum(skb, new_mpls_lse, MPLS_HLEN);
>
> - update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
> + if (skb->mac_len)
> + update_ethertype(skb, eth_hdr(skb), mpls->mpls_ethertype);
We can move all ethernet related code in this if block. for example memmove().
> if (!skb->inner_protocol)
> skb_set_inner_protocol(skb, skb->protocol);
> skb->protocol = mpls->mpls_ethertype;
> @@ -184,7 +185,6 @@ static int push_mpls(struct sk_buff *skb, struct
> sw_flow_key *key,
> static int pop_mpls(struct sk_buff *skb, struct sw_flow_key *key,
> const __be16 ethertype)
> {
> - struct ethhdr *hdr;
> int err;
>
> err = skb_ensure_writable(skb, skb->mac_len + MPLS_HLEN);
> @@ -199,11 +199,16 @@ static int pop_mpls(struct sk_buff *skb, struct
> sw_flow_key *key,
> __skb_pull(skb, MPLS_HLEN);
> skb_reset_mac_header(skb);
>
> - /* skb_mpls_header() is used to locate the ethertype
> - * field correctly in the presence of VLAN tags.
> - */
> - hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN);
> - update_ethertype(skb, hdr, ethertype);
> + if (skb->mac_len) {
> + struct ethhdr *hdr;
> +
> + /* skb_mpls_header() is used to locate the ethertype
> + * field correctly in the presence of VLAN tags.
> + */
> + hdr = (struct ethhdr *)(skb_mpls_header(skb) - ETH_HLEN);
> + update_ethertype(skb, hdr, ethertype);
> + }
same here.
