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Date:   Fri, 16 Dec 2022 12:39:56 -0700
From:   "Jason A. Donenfeld" <Jason@zx2c4.com>
To:     Johan Hovold <johan+linaro@kernel.org>
Cc:     Ard Biesheuvel <ardb@kernel.org>, linux-efi@vger.kernel.org,
        linux-kernel@vger.kernel.org, Steev Klimaszewski <steev@kali.org>,
        Bjorn Andersson <andersson@kernel.org>
Subject: Re: [PATCH] efi: random: fix NULL-deref when refreshing seed
Message-ID: <Y5zJT9Z37GSpd59l@zx2c4.com>
References: <20221216091514.6298-1-johan+linaro@kernel.org>
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On Fri, Dec 16, 2022 at 10:15:14AM +0100, Johan Hovold wrote:
> Do not try to refresh the RNG seed in case the firmware does not support
> setting variables.
> 
> This is specifically needed to prevent a NULL-pointer dereference on the
> Lenovo X13s with some firmware revisions.
> 
> Fixes: e7b813b32a42 ("efi: random: refresh non-volatile random seed when RNG is initialized")
> Reported-by: Steev Klimaszewski <steev@kali.org>
> Reported-by: Bjorn Andersson <andersson@kernel.org>
> Signed-off-by: Johan Hovold <johan+linaro@kernel.org>
> ---

Thanks very much for this, and sorry for the breakage. I'll try to get
this in before rc1 is cut, as I've got some other changes scheduled for
late in the merge window to send anyway.

Jason