[PATCH 3.16 174/370] USB: serial: ti_usb_3410_5052: fix NULL-deref at open

Ben Hutchings
2017-03-10T14:00:55Z

From: Johan Hovold <johan@kernel.org>

commit ef079936d3cd09e63612834fe2698eeada0d8e3f upstream.

Fix NULL-pointer dereference in open() should a malicious device lack
the expected endpoints:

Unable to handle kernel NULL pointer dereference at virtual address 00000030
..
[<bf06a6b0>] (ti_open [ti_usb_3410_5052]) from [<bf02e118>] (serial_port_activate+0x68/0x98 [usbserial])

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/usb/serial/ti_usb_3410_5052.c | 7 +++++++
1 file changed, 7 insertions(+)

--- a/drivers/usb/serial/ti_usb_3410_5052.c
+++ b/drivers/usb/serial/ti_usb_3410_5052.c
@@ -339,6 +339,13 @@ static int ti_startup(struct usb_serial
goto free_tdev;
}

+ if (serial->num_bulk_in < serial->num_ports ||
+ serial->num_bulk_out < serial->num_ports) {
+ dev_err(&serial->interface->dev, "missing endpoints\n");
+ status = -ENODEV;
+ goto free_tdev;
+ }
+
return 0;