HID: lg: make transfer buffers DMA capable

Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove
buffers allocated on the stack.

[jkosina@suse.cz: fix up second usage of hid_hw_raw_request(), spotted by
 0day build bot]
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

drivers/hid/hid-lg.c

@@ -756,11 +756,16 @@ static int lg_probe(struct hid_device *hdev, const struct hid_device_id *id)
 
 	/* Setup wireless link with Logitech Wii wheel */
 	if (hdev->product == USB_DEVICE_ID_LOGITECH_WII_WHEEL) {
-		unsigned char buf[] = { 0x00, 0xAF,  0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+		const unsigned char cbuf[] = { 0x00, 0xAF,  0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+		u8 *buf = kmemdup(cbuf, sizeof(cbuf), GFP_KERNEL);
 
-		ret = hid_hw_raw_request(hdev, buf[0], buf, sizeof(buf),
-					HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
+		if (!buf) {
+			ret = -ENOMEM;
+			goto err_free;
+		}
 
+		ret = hid_hw_raw_request(hdev, buf[0], buf, sizeof(cbuf),
+					HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
 		if (ret >= 0) {
 			/* insert a little delay of 10 jiffies ~ 40ms */
 			wait_queue_head_t wait;
@@ -772,9 +777,10 @@ static int lg_probe(struct hid_device *hdev, const struct hid_device_id *id)
 			buf[1] = 0xB2;
 			get_random_bytes(&buf[2], 2);
 
-			ret = hid_hw_raw_request(hdev, buf[0], buf, sizeof(buf),
+			ret = hid_hw_raw_request(hdev, buf[0], buf, sizeof(cbuf),
 					HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
 		}
+		kfree(buf);
 	}
 
 	if (drv_data->quirks & LG_FF)