media: flexcop-usb: fix endpoint sanity check

BugLink: https://bugs.launchpad.net/bugs/1873852

commit bca243b1 upstream.

commit 1b976fc6 ("media: b2c2-flexcop-usb: add sanity checking") added
an endpoint sanity check to address a NULL-pointer dereference on probe.
Unfortunately the check was done on the current altsetting which was later
changed.

Fix this by moving the sanity check to after the altsetting is changed.

Fixes: 1b976fc6 ("media: b2c2-flexcop-usb: add sanity checking")
Cc: Oliver Neukum <oneukum@suse.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>
Signed-off-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

drivers/media/usb/b2c2/flexcop-usb.c

@@ -481,6 +481,9 @@ static int flexcop_usb_init(struct flexcop_usb *fc_usb)
 		return ret;
 	}
 
+	if (fc_usb->uintf->cur_altsetting->desc.bNumEndpoints < 1)
+		return -ENODEV;
+
 	switch (fc_usb->udev->speed) {
 	case USB_SPEED_LOW:
 		err("cannot handle USB speed because it is too slow.");
@@ -514,9 +517,6 @@ static int flexcop_usb_probe(struct usb_interface *intf,
 	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;