[PATCH 4.4 113/132] media: b2c2-flexcop-usb: add sanity checking

From: Greg Kroah-Hartman
Date: Wed Nov 27 2019 - 15:38:34 EST


From: Oliver Neukum <oneukum@xxxxxxxx>

commit 1b976fc6d684e3282914cdbe7a8d68fdce19095c upstream.

The driver needs an isochronous endpoint to be present. It will
oops in its absence. Add checking for it.

Reported-by: syzbot+d93dff37e6a89431c158@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx>
Signed-off-by: Sean Young <sean@xxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/media/usb/b2c2/flexcop-usb.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/media/usb/b2c2/flexcop-usb.c
+++ b/drivers/media/usb/b2c2/flexcop-usb.c
@@ -508,6 +508,9 @@ static int flexcop_usb_probe(struct usb_
struct flexcop_device *fc = NULL;
int ret;

+ if (intf->cur_altsetting->desc.bNumEndpoints < 1)
+ return -ENODEV;
+
if ((fc = flexcop_device_kmalloc(sizeof(struct flexcop_usb))) == NULL) {
err("out of memory\n");
return -ENOMEM;