linux-kernel - Re: [PATCH v2] usb: usbip: fix a refcount leak in stub

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <16876455-ed60-65c6-1375-ac88e4209cb2@linuxfoundation.org>
Date:   Mon, 11 Apr 2022 13:38:53 -0600
From:   Shuah Khan <skhan@...uxfoundation.org>
To:     Hangyu Hua <hbh25y@...il.com>, valentina.manea.m@...il.com,
        shuah@...nel.org, gregkh@...uxfoundation.org, khoroshilov@...ras.ru
Cc:     linux-usb@...r.kernel.org, linux-kernel@...r.kernel.org,
        Shuah Khan <skhan@...uxfoundation.org>
Subject: Re: [PATCH v2] usb: usbip: fix a refcount leak in stub_probe()

On 4/10/22 11:29 PM, Hangyu Hua wrote:
> On 2022/4/8 23:04, Shuah Khan wrote:
>> On 4/7/22 7:59 PM, Hangyu Hua wrote:
>>> Hi Shuah,
>>>
>>> I find this by code review. Do i really need to add this to commit log? This look like a little weird.
>>>
>>
>> Great. Good find.
>>
>> It is important to understand how the problem is found. Please add it
>> the change log. We usually expect dmesg or such info. that revealed
>> refcount leak, since this one is found during code review, we would
>> like to see that information the commit log.
>>
>> Also please remember to avoid top posting.
> 
> I get what you meant now. But i don't know how to get a clear dmesg or any other log. The kernel will not crash because of this. I just used gdb to find that udev->dev->kobj->kref gets bigger and bigger whenever I call stub_probe with busid_priv->status = STUB_BUSID_REMOV.
> 
> Thanks for telling me the rules.
> 

There is no need to gather dmesg etc. Just add a note that you found
the problem during code review. Having complete information about why
a change is made will be helpful for future changes to this code and
somebody new trying understand the changes made to this file/routine
and why.

thanks,
-- Shuah