net: hso: fix muxed tty registration

If resource allocation and registration fail for a muxed tty device
(e.g. if there are no more minor numbers) the driver should not try to
deregister the never-registered (or already-deregistered) tty.

Fix up the error handling to avoid dereferencing a NULL pointer when
attempting to remove the character device.

Fixes: 72dc1c096c ("HSO: add option hso driver")
Cc: stable@vger.kernel.org	# 2.6.27
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Johan Hovold 2021-09-17 12:12:04 +02:00 committed by David S. Miller
parent fc0c0548c1
commit e8f69b16ee

View File

@ -2719,14 +2719,14 @@ struct hso_device *hso_create_mux_serial_device(struct usb_interface *interface,
serial = kzalloc(sizeof(*serial), GFP_KERNEL);
if (!serial)
goto exit;
goto err_free_dev;
hso_dev->port_data.dev_serial = serial;
serial->parent = hso_dev;
if (hso_serial_common_create
(serial, 1, CTRL_URB_RX_SIZE, CTRL_URB_TX_SIZE))
goto exit;
goto err_free_serial;
serial->tx_data_length--;
serial->write_data = hso_mux_serial_write_data;
@ -2742,11 +2742,9 @@ struct hso_device *hso_create_mux_serial_device(struct usb_interface *interface,
/* done, return it */
return hso_dev;
exit:
if (serial) {
tty_unregister_device(tty_drv, serial->minor);
kfree(serial);
}
err_free_serial:
kfree(serial);
err_free_dev:
kfree(hso_dev);
return NULL;