Re: [PATCH] bcache: make kobj_type structures constant

[Coly Li <colyli@suse.de>]

> 2023年4月15日 02:38，Thomas Weißschuh <linux@weissschuh.net> 写道：
> 
> Hi Coly,
> 
> On 2023-04-05 21:38:01+0800, Coly Li wrote:
>>> 2023年4月5日 01:38，Thomas Weißschuh <linux@weissschuh.net> 写道：
>>> 
>>> Hi Coly,
>>> 
>>> On 2023-02-15 00:16:03+0800, Coly Li wrote:
>>>>> 2023年2月14日 23:21，Thomas Weißschuh <linux@weissschuh.net> 写道：
>>>>> 
>>>>> On Tue, Feb 14, 2023 at 05:51:09PM +0800, Coly Li wrote:
>>>>>> 
>>>>>> 
>>>>>>> 2023年2月14日 11:13，Thomas Weißschuh <linux@weissschuh.net> 写道：
>>>>>>> 
>>>>>>> Since commit ee6d3dd4ed48 ("driver core: make kobj_type constant.")
>>>>>>> the driver core allows the usage of const struct kobj_type.
>>>>>>> 
>>>>>>> Take advantage of this to constify the structure definitions to prevent
>>>>>>> modification at runtime.
>>>>>>> 
>>>>>> 
>>>>>> How the const structure definition can prevent modification at run time?
>>>>> 
>>>>> It will be put into .rodata instead of .data by the compiler.
>>>>> The .rodata section is mapped as read-only via the pagetable.
>>>>> 
>>>>> See Documentation/security/self-protection.rst
>>>>> "Function pointers and sensitive variables must not be writable".
>>>> 
>>>> I see. Thanks for the information.
>>>> 
>>>> This patch will be added into my testing queue, and submitted later.
>>> 
>>> It seems this was not submitted.
>>> Or did I miss it?
>> 
>> No I don’t submit it yet. It is not emergent fix, and stay with other testing patches together.
>> 
>> Do you want it to go now?
> 
> No, it's not urgent.
> 
> I just assumed it should have been in next by now and thought it got
> lost along the way.
> Let's keep it with the other testing patches.

Some patches from Zheming are not simple, and I need to find time to go through them carefully.
If I am not able to handle them in time, I will submit the simple ones to Jens some time later.

Thanks.

Coly Li