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From: Suren Baghdasaryan <surenb@google.com>
Date: Mon, 26 Feb 2024 09:13:17 -0800
Message-ID: <CAJuCfpE6sJa2oHE2HrXAYuMeHd8JWd0deWa062teUs3bBRi2PA@mail.gmail.com>
Subject: Re: [PATCH v4 13/36] lib: prevent module unloading if memory is not freed
To: Vlastimil Babka <vbabka@suse.cz>
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On Mon, Feb 26, 2024 at 8:58=E2=80=AFAM Vlastimil Babka <vbabka@suse.cz> wr=
ote:
>
> On 2/21/24 20:40, Suren Baghdasaryan wrote:
> > Skip freeing module's data section if there are non-zero allocation tag=
s
> > because otherwise, once these allocations are freed, the access to thei=
r
> > code tag would cause UAF.
> >
> > Signed-off-by: Suren Baghdasaryan <surenb@google.com>
>
> I know that module unloading was never considered really supported etc.
> But should we printk something so the admin knows why it didn't unload, a=
nd
> can go check those outstanding allocations?

Yes, that sounds reasonable. I'll add a pr_warn() in the next version.
Thanks!

>
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