| From 01ec0a5f19c8c82960a07f6c7410fc9e01d7fb51 Mon Sep 17 00:00:00 2001 |
| From: Oliver Neukum <oneukum@suse.com> |
| Date: Thu, 25 Jul 2019 15:13:33 +0200 |
| Subject: HID: holtek: test for sanity of intfdata |
| |
| From: Oliver Neukum <oneukum@suse.com> |
| |
| 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@suse.cz: fix newly added spurious space] |
| Reported-by: syzbot+965152643a75a56737be@syzkaller.appspotmail.com |
| Signed-off-by: Oliver Neukum <oneukum@suse.com> |
| Signed-off-by: Jiri Kosina <jkosina@suse.cz> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| drivers/hid/hid-holtek-kbd.c | 9 +++++++-- |
| 1 file changed, 7 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/hid/hid-holtek-kbd.c |
| +++ b/drivers/hid/hid-holtek-kbd.c |
| @@ -126,9 +126,14 @@ static int holtek_kbd_input_event(struct |
| |
| /* 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, |
