ncpfs: use memdup_user()

Remove open-coded memdup_user()

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ncpfs/ioctl.c b/fs/ncpfs/ioctl.c
index f54360f..fa038df 100644
--- a/fs/ncpfs/ioctl.c
+++ b/fs/ncpfs/ioctl.c
@@ -660,13 +660,10 @@
 			if (user.object_name_len > NCP_OBJECT_NAME_MAX_LEN)
 				return -ENOMEM;
 			if (user.object_name_len) {
-				newname = kmalloc(user.object_name_len, GFP_USER);
-				if (!newname)
-					return -ENOMEM;
-				if (copy_from_user(newname, user.object_name, user.object_name_len)) {
-					kfree(newname);
-					return -EFAULT;
-				}
+				newname = memdup_user(user.object_name,
+						      user.object_name_len);
+				if (IS_ERR(newname))
+					return PTR_ERR(newname);
 			} else {
 				newname = NULL;
 			}
@@ -760,13 +757,9 @@
 			if (user.len > NCP_PRIVATE_DATA_MAX_LEN)
 				return -ENOMEM;
 			if (user.len) {
-				new = kmalloc(user.len, GFP_USER);
-				if (!new)
-					return -ENOMEM;
-				if (copy_from_user(new, user.data, user.len)) {
-					kfree(new);
-					return -EFAULT;
-				}
+				new = memdup_user(user.data, user.len);
+				if (IS_ERR(new))
+					return PTR_ERR(new);
 			} else {
 				new = NULL;
 			}