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Message-ID: <732eed82-18eb-c57b-fca1-e1f33f1f0499@gmail.com>
Date:   Thu, 7 Apr 2022 09:41:41 +0800
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Subject: Re: [PATCH] usb: usbip: fix a refcount leak in stub_probe()
Content-Language: en-US
To:     Shuah Khan <skhan@linuxfoundation.org>,
        valentina.manea.m@gmail.com, shuah@kernel.org,
        gregkh@linuxfoundation.org, khoroshilov@ispras.ru
Cc:     linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20220406061713.18938-1-hbh25y@gmail.com>
 <4341150b-195c-a896-1f6a-8715bbb539e2@linuxfoundation.org>
From:   Hangyu Hua <hbh25y@gmail.com>
In-Reply-To: <4341150b-195c-a896-1f6a-8715bbb539e2@linuxfoundation.org>
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Thanks. I will send a v2.

On 2022/4/7 02:13, Shuah Khan wrote:
> On 4/6/22 12:17 AM, Hangyu Hua wrote:
>> usb_get_dev is called in stub_device_alloc. When stub_probe fails after
>> that, usb_put_dev needs to be used.
>>
> 
> Thank you for the patch. Please include details on how you found
> this problem.
> 
> Nit: Change this to:
> 
> usb_get_dev() is called in stub_device_alloc(). When stub_probe() fails
> after that, usb_put_dev() needs to be called to release the reference.
> 
>> Fix this by moving usb_put_dev() to sdev_free
>>
> 
> Nit: Change this to:
> 
> Fix this by moving usb_put_dev() to sdev_free error path handling.
> 
>> Fixes: 3ff67445750a ("usbip: fix error handling in stub_probe()")
>> Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
>> ---
>>   drivers/usb/usbip/stub_dev.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/usb/usbip/stub_dev.c b/drivers/usb/usbip/stub_dev.c
>> index d8d3892e5a69..3c6d452e3bf4 100644
>> --- a/drivers/usb/usbip/stub_dev.c
>> +++ b/drivers/usb/usbip/stub_dev.c
>> @@ -393,7 +393,6 @@ static int stub_probe(struct usb_device *udev)
>>   err_port:
>>       dev_set_drvdata(&udev->dev, NULL);
>> -    usb_put_dev(udev);
>>       /* we already have busid_priv, just lock busid_lock */
>>       spin_lock(&busid_priv->busid_lock);
>> @@ -408,6 +407,7 @@ static int stub_probe(struct usb_device *udev)
>>       put_busid_priv(busid_priv);
>>   sdev_free:
>> +    usb_put_dev(udev);
>>       stub_device_free(sdev);
>>       return rc;
>>
> 
> With the above addressed:
> 
> Reviewed-by: Shuah Khan <skhan@linuxfoundation.org>
> 
> thanks,
> -- Shuah