new helper: memcpy_from_msg()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

net/decnet/af_decnet.c

diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index 25733d5..e2e2e3c 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -2032,7 +2032,7 @@
 
 		skb_reserve(skb, 64 + DN_MAX_NSP_DATA_HEADER);
 
-		if (memcpy_fromiovec(skb_put(skb, len), msg->msg_iov, len)) {
+		if (memcpy_from_msg(skb_put(skb, len), msg, len)) {
 			err = -EFAULT;
 			goto out;
 		}