ALSA: sound/usb: use memdup_user()

Remove open-coded memdup_user().

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/usx2y/us122l.c b/sound/usb/usx2y/us122l.c
index 98276aa..012ff1f 100644
--- a/sound/usb/usx2y/us122l.c
+++ b/sound/usb/usx2y/us122l.c
@@ -349,14 +349,10 @@
 	if (cmd != SNDRV_USB_STREAM_IOCTL_SET_PARAMS)
 		return -ENOTTY;
 
-	cfg = kmalloc(sizeof(*cfg), GFP_KERNEL);
-	if (!cfg)
-		return -ENOMEM;
+	cfg = memdup_user((void *)arg, sizeof(*cfg));
+	if (IS_ERR(cfg))
+		return PTR_ERR(cfg);
 
-	if (copy_from_user(cfg, (void *)arg, sizeof(*cfg))) {
-		err = -EFAULT;
-		goto free;
-	}
 	if (cfg->version != USB_STREAM_INTERFACE_VERSION) {
 		err = -ENXIO;
 		goto free;
diff --git a/sound/usb/usx2y/usX2Yhwdep.c b/sound/usb/usx2y/usX2Yhwdep.c
index 4af8740..f3d8f71 100644
--- a/sound/usb/usx2y/usX2Yhwdep.c
+++ b/sound/usb/usx2y/usX2Yhwdep.c
@@ -203,13 +203,12 @@
 
 	if (access_ok(VERIFY_READ, dsp->image, dsp->length)) {
 		struct usb_device* dev = priv->chip.dev;
-		char *buf = kmalloc(dsp->length, GFP_KERNEL);
-		if (!buf)
-			return -ENOMEM;
-		if (copy_from_user(buf, dsp->image, dsp->length)) {
-			kfree(buf);
-			return -EFAULT;
-		}
+		char *buf;
+
+		buf = memdup_user(dsp->image, dsp->length);
+		if (IS_ERR(buf))
+			return PTR_ERR(buf);
+
 		err = usb_set_interface(dev, 0, 1);
 		if (err)
 			snd_printk(KERN_ERR "usb_set_interface error \n");