Input: hanwang - validate number of endpoints before using them

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@kernel.org>
Cc: stable@vger.kernel.org	# 2.6.37
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/drivers/input/tablet/hanwang.c b/drivers/input/tablet/hanwang.c
index cd852059b99e..df4bea96d7ed 100644
--- a/drivers/input/tablet/hanwang.c
+++ b/drivers/input/tablet/hanwang.c
@@ -340,6 +340,9 @@ static int hanwang_probe(struct usb_interface *intf, const struct usb_device_id
         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) {