Revert "cdc-acm: hardening against malicious devices"

This reverts commit 2ad9d544.

Drop bogus sanity check; an interface in the active configuration will
always have a current altsetting assigned by USB core.
Acked-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20200921135951.24045-2-johan@kernel.orgSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/usb/class/cdc-acm.c

@@ -1197,9 +1197,6 @@ static int acm_probe(struct usb_interface *intf,
 		return -EINVAL;
 	}
 
-	if (!intf->cur_altsetting)
-		return -EINVAL;
-
 	if (!buflen) {
 		if (intf->cur_altsetting->endpoint &&
 				intf->cur_altsetting->endpoint->extralen &&
@@ -1253,8 +1250,6 @@ static int acm_probe(struct usb_interface *intf,
 		dev_dbg(&intf->dev, "no interfaces\n");
 		return -ENODEV;
 	}
-	if (!data_interface->cur_altsetting || !control_interface->cur_altsetting)
-		return -ENODEV;
 
 	if (data_intf_num != call_intf_num)
 		dev_dbg(&intf->dev, "Separate call control interface. That is not fully supported.\n");