Re: [PATCH] bcache: make kobj_type structures constant

[Coly Li]

> 2023年2月14日 23:21，Thomas Weißschuh <linux@xxxxxxxxxxxxxx> 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@xxxxxxxxxxxxxx> 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.

Coly Li