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Subject: Re: [PATCH v3 2/2] hexdump: add a new dump prefix DUMP_PREFIX_CUSTOM
To:     Sergey Senozhatsky <senozhatsky@chromium.org>
Cc:     Petr Mladek <pmladek@suse.com>,
        Steven Rostedt <rostedt@goodmis.org>,
        John Ogness <john.ogness@linutronix.de>,
        linux-kernel@vger.kernel.org,
        Zhen Lei <thunder.leizhen@huawei.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Kees Cook <keescook@chromium.org>,
        linux-hardening@vger.kernel.org
References: <20230811074922.1388-1-thunder.leizhen@huaweicloud.com>
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 <167a4aee-7a9d-a024-7594-97b84146196c@huaweicloud.com>
 <20230816033418.GD681074@google.com>
From:   "Leizhen (ThunderTown)" <thunder.leizhen@huaweicloud.com>
Message-ID: <5e30961c-f449-2a1b-ad92-c9720c5884e8@huaweicloud.com>
Date:   Wed, 16 Aug 2023 14:32:28 +0800
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On 2023/8/16 11:34, Sergey Senozhatsky wrote:
> On (23/08/16 11:20), Leizhen (ThunderTown) wrote:
>>> IMHO, this is pretty bad interface.
>>>
>>>   + From the user POV:
>>>
>>>     It is far from clear what values will be passed for the given
>>>     printf format. It can be docummented but...
>>>
>>>
>>>   + From the security POV:
>>>
>>>     The compiler could not check if the printk() parameters
>>>     match the format. I mean if the number of types of
>>>     the parameters are correct.
>>
>> Yes, it has these problems. So, back to v2, how about add DUMP_PREFIX_ADDRESS_LOW16?
>> Or named DUMP_PREFIX_ADDR16 or others. Or change the format of DUMP_PREFIX_ADDRESS
>> from "%p" to "%px"，Or add DUMP_PREFIX_RAWADDR. Or keep the status quo.
> 
> Linus quite likely will dislike (with passion) the idea of using %px.

OK, thanks.

> .
> 

-- 
Regards,
  Zhen Lei