[PATCH net-next,RFC 6/8] net: ipv4: place cb handling away from fraglist iterator

[Pablo Neira Ayuso <pablo@netfilter.org>]

Deal with the IPCB() area away from the fraglist iterator.

The bridge codebase has its own control buffer layout, move specific
IP control buffer into function.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
 net/ipv4/ip_output.c | 21 +++++++++++++++------
 1 file changed, 15 insertions(+), 6 deletions(-)

diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index ab39bbfe8197..1dc731d7be0e 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -526,9 +526,6 @@ static void ip_copy_metadata(struct sk_buff *to, struct sk_buff *from)
 
 	skb_copy_hash(to, from);
 
-	/* Copy the flags to each fragment. */
-	IPCB(to)->flags = IPCB(from)->flags;
-
 #ifdef CONFIG_NET_SCHED
 	to->tc_index = from->tc_index;
 #endif
@@ -583,6 +580,18 @@ void ip_fraglist_init(struct sk_buff *skb, struct iphdr *iph,
 }
 EXPORT_SYMBOL(ip_fraglist_init);
 
+static void ip_fraglist_ipcb_prepare(struct sk_buff *skb,
+				     struct ip_fraglist_iter *iter)
+{
+	struct sk_buff *to = iter->frag;
+
+	/* Copy the flags to each fragment. */
+	IPCB(to)->flags = IPCB(skb)->flags;
+
+	if (iter->offset == 0)
+		ip_options_fragment(to);
+}
+
 void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter)
 {
 	unsigned int hlen = iter->hlen;
@@ -599,8 +608,6 @@ void ip_fraglist_prepare(struct sk_buff *skb, struct ip_fraglist_iter *iter)
 	iph = iter->iph;
 	iph->tot_len = htons(frag->len);
 	ip_copy_metadata(frag, skb);
-	if (iter->offset == 0)
-		ip_options_fragment(frag);
 	iter->offset += skb->len - hlen;
 	iph->frag_off = htons(iter->offset >> 3);
 	if (frag->next)
@@ -800,8 +807,10 @@ int ip_do_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 		for (;;) {
 			/* Prepare header of the next frame,
 			 * before previous one went down. */
-			if (iter.frag)
+			if (iter.frag) {
+				ip_fraglist_ipcb_prepare(skb, &iter);
 				ip_fraglist_prepare(skb, &iter);
+			}
 
 			err = output(net, sk, skb);
 
-- 
2.11.0