From:   Song Liu <songliubraving@meta.com>
To:     Thomas Gleixner <tglx@linutronix.de>
CC:     Song Liu <songliubraving@meta.com>, Song Liu <song@kernel.org>,
        "linux-modules@vger.kernel.org" <linux-modules@vger.kernel.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Christoph Hellwig <hch@lst.de>,
        Kernel Team <kernel-team@meta.com>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Guenter Roeck <linux@roeck-us.net>,
        Christophe Leroy <christophe.leroy@csgroup.eu>
Subject: Re: [PATCH v9] module: replace module_layout with module_memory
Thread-Topic: [PATCH v9] module: replace module_layout with module_memory
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Date:   Tue, 7 Feb 2023 22:15:41 +0000
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> On Feb 7, 2023, at 2:13 AM, Thomas Gleixner <tglx@linutronix.de> wrote:
> 
> On Mon, Feb 06 2023 at 23:27, Song Liu wrote:
>>> On Feb 6, 2023, at 1:45 PM, Thomas Gleixner <tglx@linutronix.de> wrote:
>>>> +static void free_mod_mem(struct module *mod)
>>>> +{
>>>> + /* free the memory in the right order to avoid use-after-free */
>>> 
>>> How do we end up with a UAF when the ordering is different?
>> 
>> IIUC, we need remove MOD_DATA at last, which hosts "mod".
> 
> Oh. Please add a comment to that effect.
> 

Oops, I sent v10 too fast. 

Thanks,
Song