Re: [PATCH v3 2/2] usb: gadget: clear related members when goto fail

From: Hangyu Hua
Date: Thu Dec 30 2021 - 21:32:06 EST


On 2021/12/31 上午3:46, Alan Stern wrote:
> You must not do this. I never sent you an Acked-by for this patch; you
> shouldn't claim that I did.

I am sorry about this. I should read the linux kernel community rules
more carefully.

>> value = usb_gadget_probe_driver(&gadgetfs_driver);
>> if (value != 0) {
>> + dev->dev = NULL;
>> + dev->hs_config = NULL;
>> + dev->config = NULL;
>> kfree (dev->buf);
>> dev->buf = NULL;
> Why not just grep the lock and goto fail?

You are right. I will modify my patch later.

>> } else {
>> @@ -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.
>
>> fail:
>> + dev->config = NULL;
>> spin_unlock_irq (&dev->lock);
>> pr_debug ("%s: %s fail %zd, %p\n", shortname, __func__, value, dev);
>> kfree (dev->buf);
>
> Alan Stern
>

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.

Thanks. Happy new year.