[NETFILTER]: nf_conntrack: add __nf_copy() to copy members in skb

This unifies the codes to copy netfilter related datas. Note that
__nf_copy() assumes destination skb doesn't have any netfilter
related members.
Signed-off-by: Yasuyuki Kozakai <yasuyuki.kozakai@toshiba.co.jp>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/skbuff.h

@@ -1498,8 +1498,25 @@ static inline void nf_reset(struct sk_buff *skb)
 #endif
 }
 
+/* Note: This doesn't put any conntrack and bridge info in dst. */
+static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
+{
+	dst->nfct = src->nfct;
+	nf_conntrack_get(src->nfct);
+	dst->nfctinfo = src->nfctinfo;
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+	dst->nfct_reasm = src->nfct_reasm;
+	nf_conntrack_get_reasm(src->nfct_reasm);
+#endif
+#ifdef CONFIG_BRIDGE_NETFILTER
+	dst->nf_bridge  = src->nf_bridge;
+	nf_bridge_get(src->nf_bridge);
+#endif
+}
+
 #else /* CONFIG_NETFILTER */
 static inline void nf_reset(struct sk_buff *skb) {}
+static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src) {}
 #endif /* CONFIG_NETFILTER */
 
 #ifdef CONFIG_NETWORK_SECMARK

net/core/skbuff.c

@@ -422,19 +422,7 @@ struct sk_buff *skb_clone(struct sk_buff *skb, gfp_t gfp_mask)
 	C(protocol);
 	n->destructor = NULL;
 	C(mark);
-#ifdef CONFIG_NETFILTER
-	C(nfct);
-	nf_conntrack_get(skb->nfct);
-	C(nfctinfo);
-#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
-	C(nfct_reasm);
-	nf_conntrack_get_reasm(skb->nfct_reasm);
-#endif
-#ifdef CONFIG_BRIDGE_NETFILTER
-	C(nf_bridge);
-	nf_bridge_get(skb->nf_bridge);
-#endif
-#endif /*CONFIG_NETFILTER*/
+	__nf_copy(n, skb);
 #ifdef CONFIG_NET_SCHED
 	C(tc_index);
 #ifdef CONFIG_NET_CLS_ACT
@@ -483,22 +471,10 @@ static void copy_skb_header(struct sk_buff *new, const struct sk_buff *old)
 	new->tstamp	= old->tstamp;
 	new->destructor = NULL;
 	new->mark	= old->mark;
-#ifdef CONFIG_NETFILTER
-	new->nfct	= old->nfct;
-	nf_conntrack_get(old->nfct);
-	new->nfctinfo	= old->nfctinfo;
-#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
-	new->nfct_reasm = old->nfct_reasm;
-	nf_conntrack_get_reasm(old->nfct_reasm);
-#endif
+	__nf_copy(new, old);
 #if defined(CONFIG_IP_VS) || defined(CONFIG_IP_VS_MODULE)
 	new->ipvs_property = old->ipvs_property;
 #endif
-#ifdef CONFIG_BRIDGE_NETFILTER
-	new->nf_bridge	= old->nf_bridge;
-	nf_bridge_get(old->nf_bridge);
-#endif
-#endif
 #ifdef CONFIG_NET_SCHED
 #ifdef CONFIG_NET_CLS_ACT
 	new->tc_verd = old->tc_verd;