USB: gadget: validate interface OS descriptor requests
Stall the control endpoint in case provided index exceeds array size of
MAX_CONFIG_INTERFACES or when the retrieved function pointer is null.
Signed-off-by: Szymon Heidrich <szymon.heidrich@gmail.com>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 16f9e34..9315313 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -1988,6 +1988,9 @@ composite_setup(struct usb_gadget *gadget, const struct usb_ctrlrequest *ctrl)
if (w_index != 0x5 || (w_value >> 8))
break;
interface = w_value & 0xFF;
+ if (interface >= MAX_CONFIG_INTERFACES ||
+ !os_desc_cfg->interface[interface])
+ break;
buf[6] = w_index;
count = count_ext_prop(os_desc_cfg,
interface);