[PATCH 2/2] Input: usbtouchscreen - add driver_info sanity check

From: Johan Hovold
Date: Mon Jun 20 2022 - 04:51:58 EST


Add a sanity check on the device id-table driver_info field to make sure
we never access a type structure (and function pointers) outside of the
device info array (e.g. if someone fails to ifdef a device-id entry).

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
---
drivers/input/touchscreen/usbtouchscreen.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/input/touchscreen/usbtouchscreen.c b/drivers/input/touchscreen/usbtouchscreen.c
index 6683554f0e92..f90acbeea74f 100644
--- a/drivers/input/touchscreen/usbtouchscreen.c
+++ b/drivers/input/touchscreen/usbtouchscreen.c
@@ -1656,6 +1656,9 @@ static int usbtouch_probe(struct usb_interface *intf,
if (id->driver_info == DEVTYPE_IGNORE)
return -ENODEV;

+ if (id->driver_info >= DEVTYPE_COUNT)
+ return -EINVAL;
+
endpoint = usbtouch_get_input_endpoint(intf->cur_altsetting);
if (!endpoint)
return -ENXIO;
--
2.35.1