1 files changed, 23 insertions, 3 deletions

diff --git a/include/net/netlink.h b/include/net/netlink.h
index 23f27b0b3cef..1f18b47f41b4 100644
--- a/include/net/netlink.h
+++ b/include/net/netlink.h
@@ -1415,13 +1415,18 @@ static inline void *nla_memdup(const struct nlattr *src, gfp_t gfp)
 }
 
 /**
- * nla_nest_start - Start a new level of nested attributes
+ * nla_nest_start_noflag - Start a new level of nested attributes
  * @skb: socket buffer to add attributes to
  * @attrtype: attribute type of container
  *
- * Returns the container attribute
+ * This function exists for backward compatibility to use in APIs which never
+ * marked their nest attributes with NLA_F_NESTED flag. New APIs should use
+ * nla_nest_start() which sets the flag.
+ *
+ * Returns the container attribute or NULL on error
  */
-static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
+static inline struct nlattr *nla_nest_start_noflag(struct sk_buff *skb,
+                                                   int attrtype)
 {
         struct nlattr *start = (struct nlattr *)skb_tail_pointer(skb);
 
@@ -1432,6 +1437,21 @@ static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
 }
 
 /**
+ * nla_nest_start - Start a new level of nested attributes, with NLA_F_NESTED
+ * @skb: socket buffer to add attributes to
+ * @attrtype: attribute type of container
+ *
+ * Unlike nla_nest_start_noflag(), mark the nest attribute with NLA_F_NESTED
+ * flag. This is the preferred function to use in new code.
+ *
+ * Returns the container attribute or NULL on error
+ */
+static inline struct nlattr *nla_nest_start(struct sk_buff *skb, int attrtype)
+{
+        return nla_nest_start_noflag(skb, attrtype | NLA_F_NESTED);
+}
+
+/**
  * nla_nest_end - Finalize nesting of attributes
  * @skb: socket buffer the attributes are stored in
  * @start: container attribute