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Message-ID: <2251e63b-01f9-415f-bae3-9c64b7d7a7ac@huawei.com>
Date: Sat, 30 Mar 2024 15:10:14 +0800
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Subject: Re: [PATCH] misc: uacce - add the null check for the input pointer
 and its pointer members
To: Greg KH <gregkh@linuxfoundation.org>
CC: <zhangfei.gao@linaro.org>, <wangzhou1@hisilicon.com>,
	<linux-kernel@vger.kernel.org>, <linux-crypto@vger.kernel.org>,
	<fanghao11@huawei.com>, <shenyang39@huawei.com>, <liulongfang@huawei.com>,
	<qianweili@huawei.com>
References: <20240329062655.3055646-1-huangchenghai2@huawei.com>
 <2024032946-supernova-unstaffed-63ec@gregkh>
 <d6890b98-2f75-4077-b7bc-e995e9901574@huawei.com>
 <2024033032-catalyze-clip-cc53@gregkh>
From: huangchenghai <huangchenghai2@huawei.com>
In-Reply-To: <2024033032-catalyze-clip-cc53@gregkh>
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在 2024/3/30 15:01, Greg KH 写道:
> On Sat, Mar 30, 2024 at 11:34:24AM +0800, huangchenghai wrote:
>> On Fri, Mar 29, 2024 at2:34PM, Greg KH wrote:
>>
>>> On Fri, Mar 29, 2024 at 02:26:55PM +0800, Chenghai Huang wrote:
>>>> The uacce_alloc() is the member of the EXPORT_SYMBOL_GPL. Therefore, null
>>>> pointer verification is added on the pointer type input parameter and its
>>>> pointer members.
>>> I do not understand, why does the export type matter?  Just fix any
>>> callers to use this properly and send proper parameters.  What in-tree
>>> caller needs this?
>>>
>>> thanks,
>>>
>>> greg k-h
>> The interface defined by the export type seems important and the input
>> parameters need to be verified.
> The export type does not matter at all.
>
>> But I understand from your mail that this is the job of the caller.
> Exactly.
>
>> By the way, I still have a confusion. Interfaces like ioctrl, debugfs, read,
>> or write require parameter validation. so what kind of kernel interfaces require
>> parameter validation? Is there a definition?
> Some do, some do not, it depends on the situation.  If data comes from
> an untrusted source (i.e. outside the kernel), then it MUST be validated
> (remember "all input is evil"), but if it's from within the kernel,
> usually it does not.
>
> thanks,
>
> greg k-h

I get it, thank you very much.

thanks,

Chenghai