From: Oliver Neukum <oneukum@xxxxxxxx> commit 01ec0a5f19c8c82960a07f6c7410fc9e01d7fb51 upstream. The ioctl handler uses the intfdata of a second interface, which may not be present in a broken or malicious device, hence the intfdata needs to be checked for NULL. [jkosina@xxxxxxx: fix newly added spurious space] Reported-by: syzbot+965152643a75a56737be@xxxxxxxxxxxxxxxxxxxxxxxxx Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> Signed-off-by: Jiri Kosina <jkosina@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/hid/hid-holtek-kbd.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/hid/hid-holtek-kbd.c b/drivers/hid/hid-holtek-kbd.c index b3d502421b79d..0a38e8e9bc783 100644 --- a/drivers/hid/hid-holtek-kbd.c +++ b/drivers/hid/hid-holtek-kbd.c @@ -123,9 +123,14 @@ static int holtek_kbd_input_event(struct input_dev *dev, unsigned int type, /* Locate the boot interface, to receive the LED change events */ struct usb_interface *boot_interface = usb_ifnum_to_if(usb_dev, 0); + struct hid_device *boot_hid; + struct hid_input *boot_hid_input; - struct hid_device *boot_hid = usb_get_intfdata(boot_interface); - struct hid_input *boot_hid_input = list_first_entry(&boot_hid->inputs, + if (unlikely(boot_interface == NULL)) + return -ENODEV; + + boot_hid = usb_get_intfdata(boot_interface); + boot_hid_input = list_first_entry(&boot_hid->inputs, struct hid_input, list); return boot_hid_input->input->event(boot_hid_input->input, type, code, -- 2.20.1
