HID: steelseries: Fix signedness bug in steelseries_headset_arctis_1_fetch_battery()

The hid_hw_raw_request() function returns negative error codes or the
number bytes transferred.  The problem is that when it returns negative
error codes and we check if "ret < sizeof(arctis_1_battery_request)",
then the negative values are type promoted from int to high unsigned long
values and treated as success.

This was detected using Smatch:

    drivers/hid/hid-steelseries.c:393 steelseries_headset_arctis_1_fetch_battery()
    warn: error code type promoted to positive: 'ret'

Fixes: a0c76896c3fb ("HID: steelseries: Add support for Arctis 1 XBox")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Bastien Nocera <hadess@hadess.net>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

diff --git a/drivers/hid/hid-steelseries.c b/drivers/hid/hid-steelseries.c
index 43d2cf7153d79e6412799ede4b55502b6880d5fd..b3edadf42d6d91066cd993a6b89b4bec8d3f6a0e 100644 (file)
--- a/drivers/hid/hid-steelseries.c
+++ b/drivers/hid/hid-steelseries.c
@@ -390,7 +390,7 @@ static int steelseries_headset_arctis_1_fetch_battery(struct hid_device *hdev)
        ret = hid_hw_raw_request(hdev, arctis_1_battery_request[0],
                                 write_buf, sizeof(arctis_1_battery_request),
                                 HID_OUTPUT_REPORT, HID_REQ_SET_REPORT);
-       if (ret < sizeof(arctis_1_battery_request)) {
+       if (ret < (int)sizeof(arctis_1_battery_request)) {
                hid_err(hdev, "hid_hw_raw_request() failed with %d\n", ret);
                ret = -ENODATA;
        }