From 039d4ed3428cf9c2052048d177880ebd02104764 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 27 Jun 2022 15:11:41 -0700 Subject: [PATCH] Input: usbtouchscreen - add driver_info sanity check 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). Note that this also suppresses a compiler warning with -Warray-bounds (gcc-11.3.0) when compile-testing the driver without enabling any of the device type Kconfig options: drivers/input/touchscreen/usbtouchscreen.c: In function 'usbtouch_probe': drivers/input/touchscreen/usbtouchscreen.c:1668:16:warning: array subscript is outside array bounds of 'struct usbtouch_device_info[0]' [-Warray-bounds] 1668 | type = &usbtouch_dev_info[id->driver_info]; Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20220623062446.16944-1-johan@kernel.org Signed-off-by: Dmitry Torokhov --- 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 43c521f50c851..3dda6eaabdab8 100644 --- a/drivers/input/touchscreen/usbtouchscreen.c +++ b/drivers/input/touchscreen/usbtouchscreen.c @@ -1654,6 +1654,9 @@ static int usbtouch_probe(struct usb_interface *intf, if (id->driver_info == DEVTYPE_IGNORE) return -ENODEV; + if (id->driver_info >= ARRAY_SIZE(usbtouch_dev_info)) + return -ENODEV; + endpoint = usbtouch_get_input_endpoint(intf->cur_altsetting); if (!endpoint) return -ENXIO; -- 2.39.5