HID: wacom: generic: Treat serial number and related fields as unsigned

[mirror_ubuntu-bionic-kernel.git] / drivers / hid / hid-lgff.c

diff --git a/drivers/hid/hid-lgff.c b/drivers/hid/hid-lgff.c
index e1394af0ae7ba06701ad106896fb9391c417d6c0..1871cdcd1e0a8c5d93273b4dd58174efcaabdb14 100644 (file)
--- a/drivers/hid/hid-lgff.c
+++ b/drivers/hid/hid-lgff.c
@@ -127,12 +127,19 @@ static void hid_lgff_set_autocenter(struct input_dev *dev, u16 magnitude)
 
 int lgff_init(struct hid_device* hid)
 {
-       struct hid_input *hidinput = list_entry(hid->inputs.next, struct hid_input, list);
-       struct input_dev *dev = hidinput->input;
+       struct hid_input *hidinput;
+       struct input_dev *dev;
        const signed short *ff_bits = ff_joystick;
        int error;
        int i;
 
+       if (list_empty(&hid->inputs)) {
+               hid_err(hid, "no inputs found\n");
+               return -ENODEV;
+       }
+       hidinput = list_entry(hid->inputs.next, struct hid_input, list);
+       dev = hidinput->input;
+
        /* Check that the report looks ok */
        if (!hid_validate_values(hid, HID_OUTPUT_REPORT, 0, 0, 7))
                return -ENODEV;