Subject: Re: [PATCH v3 2/2] usb: gadget: clear related members when goto fail
To:     Alan Stern <stern@rowland.harvard.edu>
Cc:     balbi@kernel.org, gregkh@linuxfoundation.org, axboe@kernel.dk,
        jj251510319013@gmail.com, dan.carpenter@oracle.com,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20211230051132.21056-1-hbh25y@gmail.com>
 <20211230051132.21056-3-hbh25y@gmail.com>
 <Yc4MeIt6JygZ6CrY@rowland.harvard.edu>
 <CAOo-nLLpNfHzrOyF4P0XvFK1h+J+aZqGL+AqmZP2PG6C=rcFjg@mail.gmail.com>
 <Yc8odYb41iNuQ16J@rowland.harvard.edu>
From:   Hangyu Hua <hbh25y@gmail.com>
Message-ID: <268b05c1-846e-c229-277c-140c13fc87dc@gmail.com>
Date:   Sat, 1 Jan 2022 00:15:25 +0800
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I get that. I will fix and resubmit my patch.

Thanks again.

On 2021/12/31 下午11:57, Alan Stern wrote:
> On Fri, Dec 31, 2021 at 10:31:51AM +0800, Hangyu Hua wrote:
>> On 2021/12/31 上午3:46, Alan Stern wrote:
> 
>>>> @@ -1892,7 +1895,12 @@ dev_config (struct file *fd, const char __user *buf, size_t len, loff_t *ptr)
>>>>       }
>>>>       return value;
>>>>
>>>> +fail2:
>>>> +    dev->dev = NULL;
>>>> +fail1:
>>>> +    dev->hs_config = NULL;
>>>
>>> It is not necessary to have all these different statement labels.  You
>>> can simply have "fail:" clear all three pointers.
> 
>> I don't think so. It is not necessary to clean all three pointers if
>> some of them aren't kbuf. I think it may be better to keep their own
>> pointers.
> 
> If the pointers aren't set to a region inside kbuf then they are
> meaningless.  There is no reason to keep the old values.  It is better
> to avoid multiple unnecessary statement labels.
> 
> Alan Stern
>