[PATCH 2/7] Input: cm109 - fix NULL-deref at probe

[Johan Hovold <johan@kernel.org>]

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

Fixes: c04148f915e5 ("Input: add driver for USB VoIP phones with CM109
chipset")
Cc: stable <stable@vger.kernel.org>	# 2.6.28
Cc: Alfred E. Heggestad <aeh@db.org>

Signed-off-by: Johan Hovold <johan@kernel.org>
---
 drivers/input/misc/cm109.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/input/misc/cm109.c b/drivers/input/misc/cm109.c
index 9cc6d057c302..23c191a2a071 100644
--- a/drivers/input/misc/cm109.c
+++ b/drivers/input/misc/cm109.c
@@ -700,6 +700,10 @@ static int cm109_usb_probe(struct usb_interface *intf,
 	int error = -ENOMEM;
 
 	interface = intf->cur_altsetting;
+
+	if (interface->desc.bNumEndpoints < 1)
+		return -ENODEV;
+
 	endpoint = &interface->endpoint[0].desc;
 
 	if (!usb_endpoint_is_int_in(endpoint))
-- 
2.12.0