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

This unifies the codes to copy netfilter related datas. Before copying,
nf_copy() puts original members in destination skb.

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>

1 files changed, 13 insertions, 0 deletions

diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
index 62ab1ab07028..47c57be97d43 100644
--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -1514,9 +1514,22 @@ static inline void __nf_copy(struct sk_buff *dst, const struct sk_buff *src)
 #endif
 }
 
+static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src)
+{
+        nf_conntrack_put(dst->nfct);
+#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)
+        nf_conntrack_put_reasm(dst->nfct_reasm);
+#endif
+#ifdef CONFIG_BRIDGE_NETFILTER
+        nf_bridge_put(dst->nf_bridge);
+#endif
+        __nf_copy(dst, src);
+}
+
 #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) {}
+static inline void nf_copy(struct sk_buff *dst, const struct sk_buff *src) {}
 #endif /* CONFIG_NETFILTER */
 
 #ifdef CONFIG_NETWORK_SECMARK