diff options
| author | Jason Gerecke <jason.gerecke@wacom.com> | 2023-06-08 14:38:28 -0700 |
|---|---|---|
| committer | Benjamin Tissoires <bentiss@kernel.org> | 2023-06-26 16:09:28 +0200 |
| commit | 9a6c0e28e215535b2938c61ded54603b4e5814c5 (patch) | |
| tree | c64340fadca7b38d39e11a5b69411164ba464b53 | |
| parent | 4c2216728f688da3c4478fec23be9bd820824664 (diff) | |
HID: wacom: Use ktime_t rather than int when dealing with timestamps
Code which interacts with timestamps needs to use the ktime_t type
returned by functions like ktime_get. The int type does not offer
enough space to store these values, and attempting to use it is a
recipe for problems. In this particular case, overflows would occur
when calculating/storing timestamps leading to incorrect values being
reported to userspace. In some cases these bad timestamps cause input
handling in userspace to appear hung.
Link: https://gitlab.freedesktop.org/libinput/libinput/-/issues/901
Fixes: 17d793f3ed53 ("HID: wacom: insert timestamp to packed Bluetooth (BT) events")
CC: stable@vger.kernel.org
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Link: https://lore.kernel.org/r/20230608213828.2108-1-jason.gerecke@wacom.com
Signed-off-by: Benjamin Tissoires <bentiss@kernel.org>
| -rw-r--r-- | drivers/hid/wacom_wac.c | 6 | ||||
| -rw-r--r-- | drivers/hid/wacom_wac.h | 2 |
2 files changed, 4 insertions, 4 deletions
diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c index 2ccf83837134..174bf03908d7 100644 --- a/drivers/hid/wacom_wac.c +++ b/drivers/hid/wacom_wac.c @@ -1314,7 +1314,7 @@ static void wacom_intuos_pro2_bt_pen(struct wacom_wac *wacom) struct input_dev *pen_input = wacom->pen_input; unsigned char *data = wacom->data; int number_of_valid_frames = 0; - int time_interval = 15000000; + ktime_t time_interval = 15000000; ktime_t time_packet_received = ktime_get(); int i; @@ -1348,7 +1348,7 @@ static void wacom_intuos_pro2_bt_pen(struct wacom_wac *wacom) if (number_of_valid_frames) { if (wacom->hid_data.time_delayed) time_interval = ktime_get() - wacom->hid_data.time_delayed; - time_interval /= number_of_valid_frames; + time_interval = div_u64(time_interval, number_of_valid_frames); wacom->hid_data.time_delayed = time_packet_received; } @@ -1359,7 +1359,7 @@ static void wacom_intuos_pro2_bt_pen(struct wacom_wac *wacom) bool range = frame[0] & 0x20; bool invert = frame[0] & 0x10; int frames_number_reversed = number_of_valid_frames - i - 1; - int event_timestamp = time_packet_received - frames_number_reversed * time_interval; + ktime_t event_timestamp = time_packet_received - frames_number_reversed * time_interval; if (!valid) continue; diff --git a/drivers/hid/wacom_wac.h b/drivers/hid/wacom_wac.h index 1a40bb8c5810..ee21bb260f22 100644 --- a/drivers/hid/wacom_wac.h +++ b/drivers/hid/wacom_wac.h @@ -324,7 +324,7 @@ struct hid_data { int ps_connected; bool pad_input_event_flag; unsigned short sequence_number; - int time_delayed; + ktime_t time_delayed; }; struct wacom_remote_data { |