From 5abfe85c1d4694d5d4bbd13ecc166262b937adf0 Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Fri, 22 Aug 2014 16:16:05 -0400 Subject: [PATCH] HID: logitech-dj: prevent false errors to be shown Commit "HID: logitech: perform bounds checking on device_id early enough" unfortunately leaks some errors to dmesg which are not real ones: - if the report is not a DJ one, then there is not point in checking the device_id - the receiver (index 0) can also receive some notifications which can be safely ignored given the current implementation Move out the test regarding the report_id and also discards printing errors when the receiver got notified. Fixes: ad3e14d7c5268c2e24477c6ef54bbdf88add5d36 Cc: stable@vger.kernel.org Reported-and-tested-by: Markus Trippelsdorf Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-logitech-dj.c | 43 ++++++++++++++++++++--------------- drivers/hid/hid-logitech-dj.h | 1 + 2 files changed, 26 insertions(+), 18 deletions(-) diff --git a/drivers/hid/hid-logitech-dj.c b/drivers/hid/hid-logitech-dj.c index b7ba82960c79..9bf8637747a5 100644 --- a/drivers/hid/hid-logitech-dj.c +++ b/drivers/hid/hid-logitech-dj.c @@ -656,7 +656,6 @@ static int logi_dj_raw_event(struct hid_device *hdev, struct dj_receiver_dev *djrcv_dev = hid_get_drvdata(hdev); struct dj_report *dj_report = (struct dj_report *) data; unsigned long flags; - bool report_processed = false; dbg_hid("%s, size:%d\n", __func__, size); @@ -683,34 +682,42 @@ static int logi_dj_raw_event(struct hid_device *hdev, * device (via hid_input_report() ) and return 1 so hid-core does not do * anything else with it. */ + + /* case 1) */ + if (data[0] != REPORT_ID_DJ_SHORT) + return false; + if ((dj_report->device_index < DJ_DEVICE_INDEX_MIN) || (dj_report->device_index > DJ_DEVICE_INDEX_MAX)) { - dev_err(&hdev->dev, "%s: invalid device index:%d\n", + /* + * Device index is wrong, bail out. + * This driver can ignore safely the receiver notifications, + * so ignore those reports too. + */ + if (dj_report->device_index != DJ_RECEIVER_INDEX) + dev_err(&hdev->dev, "%s: invalid device index:%d\n", __func__, dj_report->device_index); return false; } spin_lock_irqsave(&djrcv_dev->lock, flags); - if (dj_report->report_id == REPORT_ID_DJ_SHORT) { - switch (dj_report->report_type) { - case REPORT_TYPE_NOTIF_DEVICE_PAIRED: - case REPORT_TYPE_NOTIF_DEVICE_UNPAIRED: - logi_dj_recv_queue_notification(djrcv_dev, dj_report); - break; - case REPORT_TYPE_NOTIF_CONNECTION_STATUS: - if (dj_report->report_params[CONNECTION_STATUS_PARAM_STATUS] == - STATUS_LINKLOSS) { - logi_dj_recv_forward_null_report(djrcv_dev, dj_report); - } - break; - default: - logi_dj_recv_forward_report(djrcv_dev, dj_report); + switch (dj_report->report_type) { + case REPORT_TYPE_NOTIF_DEVICE_PAIRED: + case REPORT_TYPE_NOTIF_DEVICE_UNPAIRED: + logi_dj_recv_queue_notification(djrcv_dev, dj_report); + break; + case REPORT_TYPE_NOTIF_CONNECTION_STATUS: + if (dj_report->report_params[CONNECTION_STATUS_PARAM_STATUS] == + STATUS_LINKLOSS) { + logi_dj_recv_forward_null_report(djrcv_dev, dj_report); } - report_processed = true; + break; + default: + logi_dj_recv_forward_report(djrcv_dev, dj_report); } spin_unlock_irqrestore(&djrcv_dev->lock, flags); - return report_processed; + return true; } static int logi_dj_probe(struct hid_device *hdev, diff --git a/drivers/hid/hid-logitech-dj.h b/drivers/hid/hid-logitech-dj.h index 4a4000340ce1..daeb0aa4bee9 100644 --- a/drivers/hid/hid-logitech-dj.h +++ b/drivers/hid/hid-logitech-dj.h @@ -27,6 +27,7 @@ #define DJ_MAX_PAIRED_DEVICES 6 #define DJ_MAX_NUMBER_NOTIFICATIONS 8 +#define DJ_RECEIVER_INDEX 0 #define DJ_DEVICE_INDEX_MIN 1 #define DJ_DEVICE_INDEX_MAX 6 -- 2.20.1