[PATCH 3.10 092/268] Input: kbtab - validate number of endpoints before using them

Willy Tarreau
2017-06-19T18:34:16Z

From: Johan Hovold <johan@kernel.org>

commit cb1b494663e037253337623bf1ef2df727883cb7 upstream.

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

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/input/tablet/kbtab.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/input/tablet/kbtab.c b/drivers/input/tablet/kbtab.c
index 3fba74b..f0d5326 100644
--- a/drivers/input/tablet/kbtab.c
+++ b/drivers/input/tablet/kbtab.c
@@ -123,6 +123,9 @@ static int kbtab_probe(struct usb_interface *intf, const struct usb_device_id *i
struct input_dev *input_dev;
int error = -ENOMEM;

+ if (intf->cur_altsetting->desc.bNumEndpoints < 1)
+ return -ENODEV;
+
kbtab = kzalloc(sizeof(struct kbtab), GFP_KERNEL);
input_dev = input_allocate_device();
if (!kbtab || !input_dev)
--
2.8.0.rc2.1.gbe9624a