act_bpf: Use kmemdup instead of duplicating it in tcf_bpf_init_from_ops

Replace calls to kmalloc followed by a memcpy with a direct call to
kmemdup.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
index 06f743d..6203eb0 100644
--- a/net/sched/act_bpf.c
+++ b/net/sched/act_bpf.c
@@ -196,12 +196,10 @@ static int tcf_bpf_init_from_ops(struct nlattr **tb, struct tcf_bpf_cfg *cfg)
 	if (bpf_size != nla_len(tb[TCA_ACT_BPF_OPS]))
 		return -EINVAL;
 
-	bpf_ops = kzalloc(bpf_size, GFP_KERNEL);
+	bpf_ops = kmemdup(nla_data(tb[TCA_ACT_BPF_OPS]), bpf_size, GFP_KERNEL);
 	if (bpf_ops == NULL)
 		return -ENOMEM;
 
-	memcpy(bpf_ops, nla_data(tb[TCA_ACT_BPF_OPS]), bpf_size);
-
 	fprog_tmp.len = bpf_num_ops;
 	fprog_tmp.filter = bpf_ops;