diff mbox series

holtek: test for sanity of intfdata

Message ID 20190725131333.26192-1-oneukum@suse.com (mailing list archive)
State New, archived
Delegated to: Jiri Kosina
Headers show
Series holtek: test for sanity of intfdata | expand

Commit Message

Oliver Neukum July 25, 2019, 1:13 p.m. UTC
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.

Reported-by: syzbot+965152643a75a56737be@syzkaller.appspotmail.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
---
 drivers/hid/hid-holtek-kbd.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

Comments

Jiri Kosina Aug. 5, 2019, 12:19 p.m. UTC | #1
On Thu, 25 Jul 2019, Oliver Neukum wrote:

> 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.
> 
> Reported-by: syzbot+965152643a75a56737be@syzkaller.appspotmail.com
> Signed-off-by: Oliver Neukum <oneukum@suse.com>

Applied, thanks Oliver.
diff mbox series

Patch

diff --git a/drivers/hid/hid-holtek-kbd.c b/drivers/hid/hid-holtek-kbd.c
index b3d502421b79..67ce75dfa9a4 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 = usb_get_intfdata(boot_interface);
-	struct hid_input *boot_hid_input = list_first_entry(&boot_hid->inputs,
+	struct hid_device *boot_hid;
+	struct hid_input *boot_hid_input;
+
+	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,