Re: [PATCH V3] staging: dgap: implement error handling in dgap_tty_register()

DaeSeok Youn
2014-05-19T09:45:15Z

2014-05-19 18:39 GMT+09:00 DaeSeok Youn <daeseok.youn@gmail.com>:
> 2014-05-19 17:02 GMT+09:00 Dan Carpenter <dan.carpenter@oracle.com>:
>> Nice, but it needs a couple style improvements below.
>>
>> On Mon, May 19, 2014 at 11:10:30AM +0900, Daeseok Youn wrote:
>>> + brd->dgap_major_serial_registered = TRUE;
>>> + dgap_boards_by_major[brd->serial_driver->major] = brd;
>>> + brd->dgap_serial_major = brd->serial_driver->major;
>>> +
>>> brd->dgap_major_transparent_print_registered = TRUE;
>>> dgap_boards_by_major[brd->print_driver->major] = brd;
>>> brd->dgap_transparent_print_major = brd->print_driver->major;
>>>
>>> return rc;
>>
>> return 0;
> OK. I will remove "int rc = 0" line and change "return rc" to "return 0"
Oh.. just remove the initialization to zero.
>
>>
>>> +
>>> +unregister_serial_drv:
>>> + tty_unregister_driver(brd->serial_driver);
>>> +free_print_ttys:
>>> + kfree(brd->print_driver->ttys);
>>> + brd->print_driver->ttys = NULL;
>>
>> This label isn't needed. Just goto free_print_drv, because that will
>> free the brd->print_driver->ttys in destruct_tty_driver().
>> I do like how you noticed the double free and avoided it by setting
>> brd->serial_driver->ttys to NULL, so your patch doesn't introduce a
>> double free bug.
> Yes, just goto free_print_drv.
>
> Thanks for review.
>
> Regards,
> Daeseok Youn
>>
>>> +free_print_drv:
>>> + put_tty_driver(brd->print_driver);
>>> +free_serial_ttys:
>>> + kfree(brd->serial_driver->ttys);
>>> + brd->serial_driver->ttys = NULL;
>>
>> Same for this.
>>
>>> +free_serial_drv:
>>> + put_tty_driver(brd->serial_driver);
>>> +
>>> + return rc;
>>
>> regards,
>> dan carpenter