Re: [PATCH v3 8/8] HID: wacom: do not use 'driver_data'
From: sashiko-bot@kernel.org
Date: 2026-07-27 15:18:16
Thank you for your contribution! Sashiko AI review found 2 potential issue(s) to consider: New issues: - [Critical] Removal of driver_data breaks dynamic device binding via sysfs 'new_id', preventing testing of unknown/clone devices. Pre-existing issues: - [High] Missing cancellation of `wacom->init_work` on the error path for wireless monitors leads to a UAF. --
--- Patch [8]: [PATCH v3 8/8] HID: wacom: do not use 'driver_data' ---commit 147dba29dc34be167b7150ce20799c7b7dd39442 Author: Pawel Zalewski (The Capable Hub) [off-list ref] HID: wacom: do not use 'driver_data' This patch removes the use of driver_data for looking up product features in the wacom driver. It instead looks up wacom_features directly by product ID to reduce macro complexity and simplify the code. [ ... ]
quoted hunk ↗ jump to hunk
diff --git a/drivers/hid/wacom_sys.c b/drivers/hid/wacom_sys.c index 834519751a5cf..4514b2762cc33 100644 --- a/drivers/hid/wacom_sys.c +++ b/drivers/hid/wacom_sys.c@@ -2848,7 +2845,7 @@ static int wacom_probe(struct hid_device *hdev, wacom_wac = &wacom->wacom_wac; - const struct wacom_features *id_features = get_wacom_features(id->driver_data); + const struct wacom_features *id_features = get_wacom_features(id->product);
[Severity: Critical]
Does removing driver_data introduce a regression for dynamic device binding
via sysfs 'new_id'?
By strictly using get_wacom_features(id->product), the mechanism for injecting
unknown product IDs seems rendered unusable because the injected PID won't match
any entry in the static wacom_features_table. Previously, couldn't users pass a
feature table index via driver_data to test unknown or clone devices?
[Severity: High]
This is a pre-existing issue, but is there a missing cancellation of
wacom->init_work on the error path for wireless monitors?
drivers/hid/wacom_sys.c:wacom_parse_and_register() {
...
if (features->device_type & WACOM_DEVICETYPE_WL_MONITOR) {
error = hid_hw_open(hdev);
if (error) {
hid_err(hdev, "hw open failed\n");
goto fail_hw_stop;
}
}
...
}
In wacom_parse_and_register(), wacom_query_tablet_data() schedules
wacom->init_work. If hid_hw_open() subsequently fails for a wireless monitor
(WACOM_DEVICETYPE_WL_MONITOR), the error path jumps to fail_hw_stop and
returns without calling cancel_delayed_work_sync(&wacom->init_work).
Because the wacom structure is managed by devres and will be freed upon probe
failure, could this result in a use-after-free when init_work executes later?
--
Sashiko AI review · https://sashiko.dev/#/patchset/20260727-mod-devicetable-hid_device_id-v3-0-980896ca283e@thegoodpenguin.co.uk?part=8