From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7B6CA174EE5; Tue, 28 May 2024 19:08:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716923298; cv=none; b=JIP6r1wDhi3hhJGkSxFAacAl0oykmJU1MRzhXtw1CYJ8ouOvPUAPrCKT2KM4nrXTJquQWOrDGj1ujVJNUqxxkuRs3IkitxtjQwh5iUmpc/baTNTYQ+FbR1SQEtNizrQOWeTxZLr1ILPt7Dops9hGjTmDMGTJJTH88nw39kny064= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1716923298; c=relaxed/simple; bh=rBmJsC3tlJj0b/3feGRs8G87U9Ytom71szWqyOUqoDw=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=o29S48j+nTcc9ubdVFtbmAvhGpQ18xBgDgYR2cdgttW3ntWG6k3RPh9TuWcwARPKXI2QoOjp9N462riW7pKpTweje9LK7h9sA5VjI37VJNHChQn/Xt6QjjTEhJyM8G09dwVCYd97yykJuGSeIFcnqH7O/HNrlDjAPeGeZB+of5E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=J/LCwUPy; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="J/LCwUPy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 018F6C3277B; Tue, 28 May 2024 19:08:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1716923298; bh=rBmJsC3tlJj0b/3feGRs8G87U9Ytom71szWqyOUqoDw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=J/LCwUPyL2WBoKc70nb7fKrFT0/9KhAXJFpvafiAa0H+E2GCgZ84xKwLEhWgSqxEv tuTIghJqks6QQdQzVqUVTUXojhPrWDCLPrCh5hoWFI/JuqQLowiGmgLMHOS3P/f8fs IwtclGTfAhh47nUABPE1mTN65wo03yW6E6IB6Jwo= Date: Tue, 28 May 2024 21:08:22 +0200 From: Greg Kroah-Hartman To: Michal Hocko Cc: Nikolay Borisov , cve@kernel.org, linux-kernel@vger.kernel.org, linux-cve-announce@vger.kernel.org Subject: Re: CVE-2024-35802: x86/sev: Fix position dependent variable references in startup code Message-ID: <2024052814-bubbly-ramp-2d8e@gregkh> References: <2024051738-CVE-2024-35802-959d@gregkh> Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, May 28, 2024 at 10:51:52AM +0200, Michal Hocko wrote: > On Thu 23-05-24 14:14:57, Nikolay Borisov wrote: > [...] > > I'd like to dispute this CVE since it doesn't constitute a security related > > bug. Sure, it might crash a SEV guest during boot but it doesn't constitute > > a security issue per-se. > > Let me add analysis by Joerg here: > : This is not a security issue. The patch works around clangs compiler behavior > : where it inserts absolute references to kernel addresses. This breaks kernel > : boot because at the time this code runs the kernel still runs direct-mapped and > : needs to rely on RIP-relative addressing only. > : > : Any breakage there would be detected at early boot of the kernel by a fatal > : crash, which can not be exploited. Also, our kernels are not compiled with > : clang, so from that perspective this is also not an issue for us either. > > So this is a functional fix for clang builds. Thanks for the review, now rejected. greg k-h