USB: cdc-acm: always claim data interface

Make sure to always claim the data interface and bail out if binding
fails.

Note that the driver had a check to verify that the data interface was
not already bound to a driver but would not detect other failures (e.g.
if the interface was not authorised).

Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20210322155318.9837-8-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c
index 1f0fcab..5ce525d 100644 (file)
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -1309,13 +1309,6 @@ skip_normal_probe:
        if (!combined_interfaces && intf != control_interface)
                return -ENODEV;
 
-       if (!combined_interfaces && usb_interface_claimed(data_interface)) {
-               /* valid in this context */
-               dev_dbg(&intf->dev, "The data interface isn't available\n");
-               return -EBUSY;
-       }
-
-
        if (data_interface->cur_altsetting->desc.bNumEndpoints < 2 ||
            control_interface->cur_altsetting->desc.bNumEndpoints == 0)
                return -EINVAL;
@@ -1499,7 +1492,11 @@ skip_countries:
        acm->line.bDataBits = 8;
        acm_set_line(acm, &acm->line);
 
-       usb_driver_claim_interface(&acm_driver, data_interface, acm);
+       if (!acm->combined_interfaces) {
+               rv = usb_driver_claim_interface(&acm_driver, data_interface, acm);
+               if (rv)
+                       goto err_remove_files;
+       }
 
        tty_dev = tty_port_register_device(&acm->port, acm_tty_driver, minor,
                        &control_interface->dev);
@@ -1521,6 +1518,7 @@ err_release_data_interface:
                usb_set_intfdata(data_interface, NULL);
                usb_driver_release_interface(&acm_driver, data_interface);
        }
+err_remove_files:
        if (acm->country_codes) {
                device_remove_file(&acm->control->dev,
                                &dev_attr_wCountryCodes);