Wrap several common instances of:
	kmemdup(nla_data(attr), nla_len(attr), GFP_KERNEL);
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
        return tmp;
 }
 
+/**
+ * nla_memdup - duplicate attribute memory (kmemdup)
+ * @src: netlink attribute to duplicate from
+ * @gfp: GFP mask
+ */
+static inline void *nla_memdup(const struct nlattr *src, gfp_t gfp)
+{
+       return kmemdup(nla_data(src), nla_len(src), gfp);
+}
+
 /**
  * nla_nest_start - Start a new level of nested attributes
  * @skb: socket buffer to add attributes to
 
                return PTR_ERR(fp);
 
        if (tb[TCA_ACT_BPF_NAME]) {
-               name = kmemdup(nla_data(tb[TCA_ACT_BPF_NAME]),
-                              nla_len(tb[TCA_ACT_BPF_NAME]),
-                              GFP_KERNEL);
+               name = nla_memdup(tb[TCA_ACT_BPF_NAME], GFP_KERNEL);
                if (!name) {
                        bpf_prog_put(fp);
                        return -ENOMEM;
 
                return PTR_ERR(fp);
 
        if (tb[TCA_BPF_NAME]) {
-               name = kmemdup(nla_data(tb[TCA_BPF_NAME]),
-                              nla_len(tb[TCA_BPF_NAME]),
-                              GFP_KERNEL);
+               name = nla_memdup(tb[TCA_BPF_NAME], GFP_KERNEL);
                if (!name) {
                        bpf_prog_put(fp);
                        return -ENOMEM;
 
 
        i = 0;
        nla_for_each_nested(attr, attr_filter, rem) {
-               filter[i].filter = kmemdup(nla_data(attr), nla_len(attr),
-                                          GFP_KERNEL);
+               filter[i].filter = nla_memdup(attr, GFP_KERNEL);
                filter[i].len = nla_len(attr);
                i++;
        }