[PATCH 3.2 27/95] Input: iforce - validate number of endpoints before using them

From: Ben Hutchings
Date: Sun Jul 16 2017 - 10:49:34 EST


3.2.91-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Johan Hovold <johan@xxxxxxxxxx>

commit 59cf8bed44a79ec42303151dd014fdb6434254bb upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer or accessing memory that lie beyond the end of the endpoint
array should a malicious device lack the expected endpoints.

Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
drivers/input/joystick/iforce/iforce-usb.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/input/joystick/iforce/iforce-usb.c
+++ b/drivers/input/joystick/iforce/iforce-usb.c
@@ -138,6 +138,9 @@ static int iforce_usb_probe(struct usb_i

interface = intf->cur_altsetting;

+ if (interface->desc.bNumEndpoints < 2)
+ return -ENODEV;
+
epirq = &interface->endpoint[0].desc;
epout = &interface->endpoint[1].desc;