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Subject: Re: [PATCH] cxl: Fix kobject memleak
To:     Andrew Donnellan <ajd@linux.ibm.com>, <fbarrat@linux.ibm.com>,
        <arnd@arndb.de>, <gregkh@linuxfoundation.org>
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        <linuxppc-dev@lists.ozlabs.org>, <linux-kernel@vger.kernel.org>
References: <20200602120733.5943-1-wanghai38@huawei.com>
 <72e2df75-b74b-cbd4-4cbe-c0f994d4c4f7@linux.ibm.com>
From:   "wanghai (M)" <wanghai38@huawei.com>
Message-ID: <a9ecd617-c541-aeb1-2e94-93abba475279@huawei.com>
Date:   Wed, 3 Jun 2020 19:57:39 +0800
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在 2020/6/3 19:33, Andrew Donnellan 写道:
> On 2/6/20 10:07 pm, Wang Hai wrote:
>> Currently the error return path from kobject_init_and_add() is not
>> followed by a call to kobject_put() - which means we are leaking
>> the kobject.
>>
>> Fix it by adding a call to kobject_put() in the error path of
>> kobject_init_and_add().
>>
>> Fixes: b087e6190ddc ("cxl: Export optional AFU configuration record 
>> in sysfs")
>> Reported-by: Hulk Robot <hulkci@huawei.com>
>> Signed-off-by: Wang Hai <wanghai38@huawei.com>
>
> Thanks for the fix!
>
> I note that the err1 label returns without calling kfree(cr) and I 
> can't see a reason why we do that - so perhaps we should remove the 
> return statement in err1: so it falls through?
>
kfree(cr) can be called when 
kobject_put()-->kobject_release()-->kobject_cleanup()-->kobj_type->release() 
is called.  The kobj_type here is afu_config_record_type


Thanks,

Wang Hai