Linux-libre 4.4-gnupck-4.4-gnu

1 files changed, 43 insertions, 13 deletions

diff --git a/include/net/dst.h b/include/net/dst.h
index 9261d9283..c7329dcd9 100644
--- a/include/net/dst.h
+++ b/include/net/dst.h
@@ -45,7 +45,7 @@ struct dst_entry {
 	void			*__pad1;
 #endif
 	int			(*input)(struct sk_buff *);
-	int			(*output)(struct sock *sk, struct sk_buff *skb);
+	int			(*output)(struct net *net, struct sock *sk, struct sk_buff *skb);
 
 	unsigned short		flags;
 #define DST_HOST		0x0001
@@ -322,6 +322,39 @@ static inline void skb_dst_force(struct sk_buff *skb)
 	}
 }
 
+/**
+ * dst_hold_safe - Take a reference on a dst if possible
+ * @dst: pointer to dst entry
+ *
+ * This helper returns false if it could not safely
+ * take a reference on a dst.
+ */
+static inline bool dst_hold_safe(struct dst_entry *dst)
+{
+	if (dst->flags & DST_NOCACHE)
+		return atomic_inc_not_zero(&dst->__refcnt);
+	dst_hold(dst);
+	return true;
+}
+
+/**
+ * skb_dst_force_safe - makes sure skb dst is refcounted
+ * @skb: buffer
+ *
+ * If dst is not yet refcounted and not destroyed, grab a ref on it.
+ */
+static inline void skb_dst_force_safe(struct sk_buff *skb)
+{
+	if (skb_dst_is_noref(skb)) {
+		struct dst_entry *dst = skb_dst(skb);
+
+		if (!dst_hold_safe(dst))
+			dst = NULL;
+
+		skb->_skb_refdst = (unsigned long)dst;
+	}
+}
+
 
 /**
  *	__skb_tunnel_rx - prepare skb for rx reinsert
@@ -365,10 +398,10 @@ static inline void skb_tunnel_rx(struct sk_buff *skb, struct net_device *dev,
 	__skb_tunnel_rx(skb, dev, net);
 }
 
-int dst_discard_sk(struct sock *sk, struct sk_buff *skb);
+int dst_discard_out(struct net *net, struct sock *sk, struct sk_buff *skb);
 static inline int dst_discard(struct sk_buff *skb)
 {
-	return dst_discard_sk(skb->sk, skb);
+	return dst_discard_out(&init_net, skb->sk, skb);
 }
 void *dst_alloc(struct dst_ops *ops, struct net_device *dev, int initial_ref,
 		int initial_obsolete, unsigned short flags);
@@ -454,13 +487,9 @@ static inline void dst_set_expires(struct dst_entry *dst, int timeout)
 }
 
 /* Output packet to network from transport.  */
-static inline int dst_output_sk(struct sock *sk, struct sk_buff *skb)
-{
-	return skb_dst(skb)->output(sk, skb);
-}
-static inline int dst_output(struct sk_buff *skb)
+static inline int dst_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 {
-	return dst_output_sk(skb->sk, skb);
+	return skb_dst(skb)->output(net, sk, skb);
 }
 
 /* Input packet from network to transport.  */
@@ -489,7 +518,8 @@ struct flowi;
 #ifndef CONFIG_XFRM
 static inline struct dst_entry *xfrm_lookup(struct net *net,
 					    struct dst_entry *dst_orig,
-					    const struct flowi *fl, struct sock *sk,
+					    const struct flowi *fl,
+					    const struct sock *sk,
 					    int flags)
 {
 	return dst_orig;
@@ -498,7 +528,7 @@ static inline struct dst_entry *xfrm_lookup(struct net *net,
 static inline struct dst_entry *xfrm_lookup_route(struct net *net,
 						  struct dst_entry *dst_orig,
 						  const struct flowi *fl,
-						  struct sock *sk,
+						  const struct sock *sk,
 						  int flags)
 {
 	return dst_orig;
@@ -511,11 +541,11 @@ static inline struct xfrm_state *dst_xfrm(const struct dst_entry *dst)
 
 #else
 struct dst_entry *xfrm_lookup(struct net *net, struct dst_entry *dst_orig,
-			      const struct flowi *fl, struct sock *sk,
+			      const struct flowi *fl, const struct sock *sk,
 			      int flags);
 
 struct dst_entry *xfrm_lookup_route(struct net *net, struct dst_entry *dst_orig,
-				    const struct flowi *fl, struct sock *sk,
+				    const struct flowi *fl, const struct sock *sk,
 				    int flags);
 
 /* skb attached with this dst needs transformation if dst->xfrm is valid */