[PATCH 4.4 062/117] USB: visor: fix null-deref at probe

Greg Kroah-Hartman
2016-02-14T23:14:52Z

From: Johan Hovold <johan@kernel.org>

commit cac9b50b0d75a1d50d6c056ff65c005f3224c8e0 upstream.

Fix null-pointer dereference at probe should a (malicious) Treo device
lack the expected endpoints.

Specifically, the Treo port-setup hack was dereferencing the bulk-in and
interrupt-in urbs without first making sure they had been allocated by
core.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/usb/serial/visor.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/drivers/usb/serial/visor.c
+++ b/drivers/usb/serial/visor.c
@@ -544,6 +544,11 @@ static int treo_attach(struct usb_serial
(serial->num_interrupt_in == 0))
return 0;

+ if (serial->num_bulk_in < 2 || serial->num_interrupt_in < 2) {
+ dev_err(&serial->interface->dev, "missing endpoints\n");
+ return -ENODEV;
+ }
+
/*
* It appears that Treos and Kyoceras want to use the
* 1st bulk in endpoint to communicate with the 2nd bulk out endpoint,