[PATCH 5.4 006/110] USB: serial: ir-usb: add missing endpoint sanity check

From: Greg Kroah-Hartman
Date: Thu Jan 30 2020 - 13:44:16 EST


From: Johan Hovold <johan@xxxxxxxxxx>

commit 2988a8ae7476fe9535ab620320790d1714bdad1d upstream.

Add missing endpoint sanity check to avoid dereferencing a NULL-pointer
on open() in case a device lacks a bulk-out endpoint.

Note that prior to commit f4a4cbb2047e ("USB: ir-usb: reimplement using
generic framework") the oops would instead happen on open() if the
device lacked a bulk-in endpoint and on write() if it lacked a bulk-out
endpoint.

Fixes: f4a4cbb2047e ("USB: ir-usb: reimplement using generic framework")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Cc: stable <stable@xxxxxxxxxxxxxxx>
Reviewed-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Johan Hovold <johan@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/usb/serial/ir-usb.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/usb/serial/ir-usb.c
+++ b/drivers/usb/serial/ir-usb.c
@@ -195,6 +195,9 @@ static int ir_startup(struct usb_serial
struct usb_irda_cs_descriptor *irda_desc;
int rates;

+ if (serial->num_bulk_in < 1 || serial->num_bulk_out < 1)
+ return -ENODEV;
+
irda_desc = irda_usb_find_class_desc(serial, 0);
if (!irda_desc) {
dev_err(&serial->dev->dev,