tty: ehv_bytechan: clean up init error handling

Straighten out the initcall error handling to avoid deregistering a
never-registered tty driver (something which would lead to a
NULL-pointer dereference) in the most unlikely event that driver
registration fails (e.g. we've run out of major numbers).

Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2017-04-26 12:30:04 +02:00 committed by Greg Kroah-Hartman
parent 1e948479b3
commit 11d4d32158

View File

@ -764,7 +764,7 @@ static int __init ehv_bc_init(void)
ehv_bc_driver = alloc_tty_driver(count);
if (!ehv_bc_driver) {
ret = -ENOMEM;
goto error;
goto err_free_bcs;
}
ehv_bc_driver->driver_name = "ehv-bc";
@ -778,24 +778,23 @@ static int __init ehv_bc_init(void)
ret = tty_register_driver(ehv_bc_driver);
if (ret) {
pr_err("ehv-bc: could not register tty driver (ret=%i)\n", ret);
goto error;
goto err_put_tty_driver;
}
ret = platform_driver_register(&ehv_bc_tty_driver);
if (ret) {
pr_err("ehv-bc: could not register platform driver (ret=%i)\n",
ret);
goto error;
goto err_deregister_tty_driver;
}
return 0;
error:
if (ehv_bc_driver) {
tty_unregister_driver(ehv_bc_driver);
put_tty_driver(ehv_bc_driver);
}
err_deregister_tty_driver:
tty_unregister_driver(ehv_bc_driver);
err_put_tty_driver:
put_tty_driver(ehv_bc_driver);
err_free_bcs:
kfree(bcs);
return ret;