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From:   Ard Biesheuvel <ardb@kernel.org>
Date:   Wed, 4 Mar 2020 16:47:34 +0100
Message-ID: <CAKv+Gu9pDiaOUipnH_=YmWNUo+G4V_HxL6rzXML0hih4yetN8w@mail.gmail.com>
Subject: Re: [PATCH] efi: fix a race and a buffer overflow while reading
 efivars via sysfs
To:     Vladis Dronov <vdronov@redhat.com>
Cc:     linux-efi <linux-efi@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Wed, 4 Mar 2020 at 16:45, Vladis Dronov <vdronov@redhat.com> wrote:
>
> Hello, Ard,
>
> > Wouldn't it be easier to pass a var_data_size stack variable into
> > efivar_entry_get(), and only update the value in 'var' if it is <=
> > 1024?
>
> I have prepared a v2 patch with an approach you suggest and will send it
> out shortly. It indeed simpler and fixes only the overflow bug mentioned.
>
> Could you, please, review it and if you like it, probably, accept it?
> In case I've implemented your idea incorrectly, could you, please,
> correct me?
>

Absolutely! Thanks for taking the time to fix these bugs, your
contributions are most welcome (and apologies if my responses
suggested otherwise)