USB: serial: fix tty-device error handling at probe

commit ca4383a3947a83286bc9b9c598a1f55e867871d7 upstream.

Add missing error handling when registering the tty device at port
probe. This avoids trying to remove an uninitialised character device
when the port device is removed.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Johan Hovold <johan@kernel.org>
Acked-by: Greg Kroah-Hartman <greg@kroah.com>
[lizf: Backported to 3.4:
 - adjust context
 - s/goto exit_with_autopm/goto exit]
Signed-off-by: Zefan Li <lizefan@huawei.com>

diff --git a/drivers/usb/serial/bus.c b/drivers/usb/serial/bus.c
index 1b596656da14fd8b7e4ed7f42ec5f4ffd9c9c77f..358d2d6d760a94362e0518f3ae91834cab68c6b1 100644 (file)
--- a/drivers/usb/serial/bus.c
+++ b/drivers/usb/serial/bus.c
@@ -52,6 +52,7 @@ static int usb_serial_device_probe(struct device *dev)
 {
        struct usb_serial_driver *driver;
        struct usb_serial_port *port;
+       struct device *tty_dev;
        int retval = 0;
        int minor;
 
@@ -76,7 +77,15 @@ static int usb_serial_device_probe(struct device *dev)
        }
 
        minor = port->number;
-       tty_register_device(usb_serial_tty_driver, minor, dev);
+       tty_dev = tty_register_device(usb_serial_tty_driver, minor, dev);
+       if (IS_ERR(tty_dev)) {
+               retval = PTR_ERR(tty_dev);
+               device_remove_file(dev, &dev_attr_port_number);
+               if (driver->port_remove)
+                       driver->port_remove(port);
+               goto exit;
+       }
+
        dev_info(&port->serial->dev->dev,
                 "%s converter now attached to ttyUSB%d\n",
                 driver->description, minor);