This is a note to let you know that I've just added the patch titled HID: lenovo: Check hid_get_drvdata() returns non NULL in lenovo_event() to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: hid-lenovo-check-hid_get_drvdata-returns-non-null-in.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 66ce38973cf971681355ef9883218cdaeb4ed1ea Author: Hans de Goede <hdegoede@xxxxxxxxxx> Date: Sun Apr 4 10:04:26 2021 +0200 HID: lenovo: Check hid_get_drvdata() returns non NULL in lenovo_event() [ Upstream commit 34348a8661e3cd67dcf6938f08c8bb77522301f7 ] 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@xxxxxxxxxx> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> 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: