[PATCH 4.9 25/88] Input: hanwang - validate number of endpoints before using them

From: Greg Kroah-Hartman
Date: Tue Mar 28 2017 - 09:11:42 EST


4.9-stable review patch. If anyone has any objections, please let me know.

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

From: Johan Hovold <johan@xxxxxxxxxx>

commit ba340d7b83703768ce566f53f857543359aa1b98 upstream.

Make sure to check the number of endpoints to avoid dereferencing a
NULL-pointer should a malicious device lack endpoints.

Fixes: bba5394ad3bd ("Input: add support for Hanwang tablets")
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/input/tablet/hanwang.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/input/tablet/hanwang.c
+++ b/drivers/input/tablet/hanwang.c
@@ -340,6 +340,9 @@ static int hanwang_probe(struct usb_inte
int error;
int i;

+ if (intf->cur_altsetting->desc.bNumEndpoints < 1)
+ return -ENODEV;
+
hanwang = kzalloc(sizeof(struct hanwang), GFP_KERNEL);
input_dev = input_allocate_device();
if (!hanwang || !input_dev) {