netfilter: nft_payload: incorrect arithmetics when fetching VLAN header bits

[platform/kernel/linux-rpi.git] / net / dsa / tag_lan9303.c

diff --git a/net/dsa/tag_lan9303.c b/net/dsa/tag_lan9303.c
index 26207ef..98d7d71 100644 (file)
--- a/net/dsa/tag_lan9303.c
+++ b/net/dsa/tag_lan9303.c
@@ -62,9 +62,10 @@ static struct sk_buff *lan9303_xmit(struct sk_buff *skb, struct net_device *dev)
        skb_push(skb, LAN9303_TAG_LEN);
 
        /* make room between MACs and Ether-Type */
-       memmove(skb->data, skb->data + LAN9303_TAG_LEN, 2 * ETH_ALEN);
+       dsa_alloc_etype_header(skb, LAN9303_TAG_LEN);
+
+       lan9303_tag = dsa_etype_header_pos_tx(skb);
 
-       lan9303_tag = (__be16 *)(skb->data + 2 * ETH_ALEN);
        tag = lan9303_xmit_use_arl(dp, skb->data) ?
                LAN9303_TAG_TX_USE_ALR :
                dp->index | LAN9303_TAG_TX_STP_OVERRIDE;
@@ -74,10 +75,8 @@ static struct sk_buff *lan9303_xmit(struct sk_buff *skb, struct net_device *dev)
        return skb;
 }
 
-static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev,
-                                  struct packet_type *pt)
+static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev)
 {
-       __be16 *lan9303_tag;
        u16 lan9303_tag1;
        unsigned int source_port;
 
@@ -87,20 +86,15 @@ static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev,
                return NULL;
        }
 
-       /* '->data' points into the middle of our special VLAN tag information:
-        *
-        * ~ MAC src   | 0x81 | 0x00 | 0xyy | 0xzz | ether type
-        *                           ^
-        *                        ->data
-        */
-       lan9303_tag = (__be16 *)(skb->data - 2);
-
-       if (lan9303_tag[0] != htons(ETH_P_8021Q)) {
-               dev_warn_ratelimited(&dev->dev, "Dropping packet due to invalid VLAN marker\n");
-               return NULL;
+       if (skb_vlan_tag_present(skb)) {
+               lan9303_tag1 = skb_vlan_tag_get(skb);
+               __vlan_hwaccel_clear_tag(skb);
+       } else {
+               skb_push_rcsum(skb, ETH_HLEN);
+               __skb_vlan_pop(skb, &lan9303_tag1);
+               skb_pull_rcsum(skb, ETH_HLEN);
        }
 
-       lan9303_tag1 = ntohs(lan9303_tag[1]);
        source_port = lan9303_tag1 & 0x3;
 
        skb->dev = dsa_master_find_slave(dev, 0, source_port);
@@ -109,13 +103,8 @@ static struct sk_buff *lan9303_rcv(struct sk_buff *skb, struct net_device *dev,
                return NULL;
        }
 
-       /* remove the special VLAN tag between the MAC addresses
-        * and the current ethertype field.
-        */
-       skb_pull_rcsum(skb, 2 + 2);
-       memmove(skb->data - ETH_HLEN, skb->data - (ETH_HLEN + LAN9303_TAG_LEN),
-               2 * ETH_ALEN);
-       skb->offload_fwd_mark = !(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU);
+       if (!(lan9303_tag1 & LAN9303_TAG_RX_TRAPPED_TO_CPU))
+               dsa_default_offload_fwd_mark(skb);
 
        return skb;
 }