Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

* 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
  [VLAN]: Fix net_device leak.
  [PPP] generic: Fix receive path data clobbering & non-linear handling
  [PPP] generic: Call skb_cow_head before scribbling over skb
  [NET] skbuff: Add skb_cow_head
  [BRIDGE]: Kill clone argument to br_flood_*
  [PPP] pppoe: Fill in header directly in __pppoe_xmit
  [PPP] pppoe: Fix data clobbering in __pppoe_xmit and return value
  [PPP] pppoe: Fix skb_unshare_check call position
  [SCTP]: Convert bind_addr_list locking to RCU
  [SCTP]: Add RCU synchronization around sctp_localaddr_list
  [PKT_SCHED]: sch_cbq.c: Shut up uninitialized variable warning
  [PKTGEN]: srcmac fix
  [IPV6]: Fix source address selection.
  [IPV4]: Just increment OutDatagrams once per a datagram.
  [IPV6]: Just increment OutDatagrams once per a datagram.
  [IPV6]: Fix unbalanced socket reference with MSG_CONFIRM.
  [NET_SCHED] protect action config/dump from irqs
  [NET]: Fix two issues wrt. SO_BINDTODEVICE.

1 files changed, 31 insertions, 9 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 93c27f71122..a656cecd373 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1352,6 +1352,22 @@ static inline int skb_clone_writable(struct sk_buff *skb, int len)
 	       skb_headroom(skb) + len <= skb->hdr_len;
 }
 
+static inline int __skb_cow(struct sk_buff *skb, unsigned int headroom,
+			    int cloned)
+{
+	int delta = 0;
+
+	if (headroom < NET_SKB_PAD)
+		headroom = NET_SKB_PAD;
+	if (headroom > skb_headroom(skb))
+		delta = headroom - skb_headroom(skb);
+
+	if (delta || cloned)
+		return pskb_expand_head(skb, ALIGN(delta, NET_SKB_PAD), 0,
+					GFP_ATOMIC);
+	return 0;
+}
+
 /**
  *	skb_cow - copy header of skb when it is required
  *	@skb: buffer to cow
@@ -1366,16 +1382,22 @@ static inline int skb_clone_writable(struct sk_buff *skb, int len)
  */
 static inline int skb_cow(struct sk_buff *skb, unsigned int headroom)
 {
-	int delta = (headroom > NET_SKB_PAD ? headroom : NET_SKB_PAD) -
-			skb_headroom(skb);
-
-	if (delta < 0)
-		delta = 0;
+	return __skb_cow(skb, headroom, skb_cloned(skb));
+}
 
-	if (delta || skb_cloned(skb))
-		return pskb_expand_head(skb, (delta + (NET_SKB_PAD-1)) &
-				~(NET_SKB_PAD-1), 0, GFP_ATOMIC);
-	return 0;
+/**
+ *	skb_cow_head - skb_cow but only making the head writable
+ *	@skb: buffer to cow
+ *	@headroom: needed headroom
+ *
+ *	This function is identical to skb_cow except that we replace the
+ *	skb_cloned check by skb_header_cloned.  It should be used when
+ *	you only need to push on some header and do not need to modify
+ *	the data.
+ */
+static inline int skb_cow_head(struct sk_buff *skb, unsigned int headroom)
+{
+	return __skb_cow(skb, headroom, skb_header_cloned(skb));
 }
 
 /**