From: Wolfram Sang <wsa@the-dreams.de>
Date: Fri, 10 Jan 2014 18:36:41 +0000 (+0100)
Subject: usb: core: add sanity checks when using bInterfaceClass with new_id
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c63fe8f6;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git

usb: core: add sanity checks when using bInterfaceClass with new_id

Check if that field is actually used and if so, bail out if it exeeds a
u8. Make it also future-proof by not requiring "exactly three"
parameters in new_id, but simply "more than two".

Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 8d989b1d3dc5..574f5a04c92d 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -60,7 +60,10 @@ ssize_t usb_store_new_id(struct usb_dynids *dynids,
 	dynid->id.idVendor = idVendor;
 	dynid->id.idProduct = idProduct;
 	dynid->id.match_flags = USB_DEVICE_ID_MATCH_DEVICE;
-	if (fields == 3) {
+	if (fields > 2 && bInterfaceClass) {
+		if (bInterfaceClass > 255)
+			return -EINVAL;
+
 		dynid->id.bInterfaceClass = (u8)bInterfaceClass;
 		dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
 	}