HID: logitech-dj: Fix error handling in logi_dj_recv_switch_to_dj_mode()

Presently, if a call to logi_dj_recv_send_report() fails, we do
not learn about the error until after sending short
HID_OUTPUT_REPORT with hid_hw_raw_request().
To handle this somewhat unlikely issue, return on error in
logi_dj_recv_send_report() (minding ugly sleep workaround) and
take into account the result of hid_hw_raw_request().

Found by Linux Verification Center (linuxtesting.org) with static
analysis tool SVACE.

Fixes: 6a9ddc897883 ("HID: logitech-dj: enable notifications on connect/disconnect")
Signed-off-by: Nikita Zhandarovich <n.zhandarovich@fintech.ru>
Link: https://lore.kernel.org/r/20230613101635.77820-1-n.zhandarovich@fintech.ru
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>

diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c
index fef67da0de537851d891742c4eae7e6e878f4cab..8afe3be683ba251617e5b5f2b9477738ce2f13d7 100644 (file)
--- a/drivers/hid/hid-logitech-dj.c
+++ b/drivers/hid/hid-logitech-dj.c
@@ -1285,6 +1285,9 @@ static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
                 * 50 msec should gives enough time to the receiver to be ready.
                 */
                msleep(50);
+
+               if (retval)
+                       return retval;
        }
 
        /*
@@ -1306,7 +1309,7 @@ static int logi_dj_recv_switch_to_dj_mode(struct dj_receiver_dev *djrcv_dev,
        buf[5] = 0x09;
        buf[6] = 0x00;
 
-       hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
+       retval = hid_hw_raw_request(hdev, REPORT_ID_HIDPP_SHORT, buf,
                        HIDPP_REPORT_SHORT_LENGTH, HID_OUTPUT_REPORT,
                        HID_REQ_SET_REPORT);