[SK_BUFF]: Introduce skb_mac_header()

For the places where we need a pointer to the mac header, it is still legal to
touch skb->mac.raw directly if just adding to, subtracting from or setting it
to another layer header.

This one also converts some more cases to skb_reset_mac_header() that my
regex missed as it had no spaces before nor after '=', ugh.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 14 insertions, 4 deletions

diff --git a/include/linux/if_ether.h b/include/linux/if_ether.h
index ab08f35cbc35..f6863fbcf334 100644
--- a/include/linux/if_ether.h
+++ b/include/linux/if_ether.h
@@ -112,7 +112,7 @@ struct ethhdr {
 
 static inline struct ethhdr *eth_hdr(const struct sk_buff *skb)
 {
-        return (struct ethhdr *)skb->mac.raw;
+        return (struct ethhdr *)skb_mac_header(skb);
 }
 
 #ifdef CONFIG_SYSCTL
diff --git a/include/linux/if_tr.h b/include/linux/if_tr.h
index 2f94cf2c7abb..046e9d95ba9a 100644
--- a/include/linux/if_tr.h
+++ b/include/linux/if_tr.h
@@ -47,7 +47,7 @@ struct trh_hdr {
 
 static inline struct trh_hdr *tr_hdr(const struct sk_buff *skb)
 {
-        return (struct trh_hdr *)skb->mac.raw;
+        return (struct trh_hdr *)skb_mac_header(skb);
 }
 #ifdef CONFIG_SYSCTL
 extern struct ctl_table tr_table[];
diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h
index d103580c72d2..544490d9d0bd 100644
--- a/include/linux/if_vlan.h
+++ b/include/linux/if_vlan.h
@@ -51,7 +51,7 @@ struct vlan_ethhdr {
 
 static inline struct vlan_ethhdr *vlan_eth_hdr(const struct sk_buff *skb)
 {
-        return (struct vlan_ethhdr *)skb->mac.raw;
+        return (struct vlan_ethhdr *)skb_mac_header(skb);
 }
 
 struct vlan_hdr {
diff --git a/include/linux/netfilter_bridge/ebt_802_3.h b/include/linux/netfilter_bridge/ebt_802_3.h
index 07f044ff1a6b..a11b0c2017fd 100644
--- a/include/linux/netfilter_bridge/ebt_802_3.h
+++ b/include/linux/netfilter_bridge/ebt_802_3.h
@@ -54,7 +54,7 @@ struct ebt_802_3_hdr {
 
 static inline struct ebt_802_3_hdr *ebt_802_3_hdr(const struct sk_buff *skb)
 {
-        return (struct ebt_802_3_hdr *)skb->mac.raw;
+        return (struct ebt_802_3_hdr *)skb_mac_header(skb);
 }
 #endif
 
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 43ab6cbf8446..dff81af454b7 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -960,6 +960,16 @@ static inline void skb_reserve(struct sk_buff *skb, int len)
         skb->tail += len;
 }
 
+static inline unsigned char *skb_mac_header(const struct sk_buff *skb)
+{
+        return skb->mac.raw;
+}
+
+static inline int skb_mac_header_was_set(const struct sk_buff *skb)
+{
+        return skb->mac.raw != NULL;
+}
+
 static inline void skb_reset_mac_header(struct sk_buff *skb)
 {
         skb->mac.raw = skb->data;