diff options
| author | Hans de Goede <hdegoede@redhat.com> | 2021-04-04 10:04:26 +0200 |
|---|---|---|
| committer | Jiri Kosina <jkosina@suse.cz> | 2021-04-07 12:48:19 +0200 |
| commit | 34348a8661e3cd67dcf6938f08c8bb77522301f7 (patch) | |
| tree | f4ba81c52cda35fc90d48b4930d42be7eb28d6c2 /drivers/hid | |
| parent | 658d04e6eb6be1601ae95d7bee92bbf4096cdc1e (diff) | |
HID: lenovo: Check hid_get_drvdata() returns non NULL in lenovo_event()
The HID lenovo probe function only attaches drvdata to one of the
USB interfaces, but lenovo_event() will get called for all USB interfaces
to which hid-lenovo is bound.
This allows a malicious device to fake being a device handled by
hid-lenovo, which generates events for which lenovo_event() has
special handling (and thus dereferences hid_get_drvdata()) on another
interface triggering a NULL pointer exception.
Add a check for hid_get_drvdata() returning NULL, avoiding this
possible NULL pointer exception.
Fixes: bc04b37ea0ec ("HID: lenovo: Add ThinkPad 10 Ultrabook Keyboard support")
Reviewed-by: Marek Behún <kabel@kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Diffstat (limited to 'drivers/hid')
| -rw-r--r-- | drivers/hid/hid-lenovo.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/hid/hid-lenovo.c b/drivers/hid/hid-lenovo.c index ee175ab54281..b2596ed37880 100644 --- a/drivers/hid/hid-lenovo.c +++ b/drivers/hid/hid-lenovo.c @@ -508,6 +508,9 @@ static int lenovo_event_cptkbd(struct hid_device *hdev, static int lenovo_event(struct hid_device *hdev, struct hid_field *field, struct hid_usage *usage, __s32 value) { + if (!hid_get_drvdata(hdev)) + return 0; + switch (hdev->product) { case USB_DEVICE_ID_LENOVO_CUSBKBD: case USB_DEVICE_ID_LENOVO_CBTKBD: |