From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 84041C10F29 for ; Wed, 18 Mar 2020 20:13:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5E3232077A for ; Wed, 18 Mar 2020 20:13:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584562428; bh=4COnoFw4zZTTnD0icQvz2MrvlZlhqnrg/n8Iz1/EMx4=; h=References:In-Reply-To:From:Date:Subject:To:Cc:List-ID:From; b=y8dGe5f3K2PVxsTbIEKot59iRJxvNkXW7t8R3y6oorq/Oc99wc2JCBy+45itFXfl6 yUcRsFVMQPK4Er56QgqZjKgTP7wlLctYkTINwejtpYlK59aFaQTvlADkSXztXo8iBR A6tnHCd4f1cwgx2B3/jD2DZn4jLE4gvVVi/GsJao= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726894AbgCRUNr (ORCPT ); Wed, 18 Mar 2020 16:13:47 -0400 Received: from mail.kernel.org ([198.145.29.99]:56714 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726733AbgCRUNq (ORCPT ); Wed, 18 Mar 2020 16:13:46 -0400 Received: from mail-qk1-f175.google.com (mail-qk1-f175.google.com [209.85.222.175]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1432020780 for ; Wed, 18 Mar 2020 20:13:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584562426; bh=4COnoFw4zZTTnD0icQvz2MrvlZlhqnrg/n8Iz1/EMx4=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=hG3NmuBEg/VNJF/IzasJRv+KrhKn+chfwwim8Zb9QBC6PEP9RK7WhXO6Ozcvpoajp o2uT+sbqXtoNk9wLw4UdvfiYnCrwx6H8PzyQgeaPmwR321fVuj+8CQWqgSHLDO71Kn CsyL8chkBDdoLaUByLk+zYQ6P3dQ0+H8ur6eIKAc= Received: by mail-qk1-f175.google.com with SMTP id s11so29804831qks.8 for ; Wed, 18 Mar 2020 13:13:46 -0700 (PDT) X-Gm-Message-State: ANhLgQ0OLz2Jg3oHXYPj31/DpUOijaAdDw0GhEI2Ey+E02Dj3u4f6hfK b+VxKf5V/6M19VpY5YDlg1w2JZnCE66tAYgvpGlTYw== X-Google-Smtp-Source: ADFU+vv74xrkhSks5Z1lN+CW1yz6xICk4LN6UCwfLkqXNiod5pEmiZcGPF75Cr+JQKJXgdsr8mOh0nXsoF/xtGiZ/nA= X-Received: by 2002:a37:634d:: with SMTP id x74mr6249300qkb.254.1584562425124; Wed, 18 Mar 2020 13:13:45 -0700 (PDT) MIME-Version: 1.0 References: <20200313110258.94A0668C4E@verein.lst.de> <20200317221743.GD20788@willie-the-truck> In-Reply-To: <20200317221743.GD20788@willie-the-truck> From: Ard Biesheuvel Date: Wed, 18 Mar 2020 16:13:33 -0400 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [Patch][Fix] crypto: arm{,64} neon: memzero_explicit aes-cbc key To: Will Deacon Cc: Torsten Duwe , Catalin Marinas , Herbert Xu , "David S. Miller" , Russell King , "open list:HARDWARE RANDOM NUMBER GENERATOR CORE" , linux-arm-kernel , Linux Kernel Mailing List Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 17 Mar 2020 at 18:17, Will Deacon wrote: > > [+Ard] > > On Fri, Mar 13, 2020 at 12:02:58PM +0100, Torsten Duwe wrote: > > From: Torsten Duwe > > > > At function exit, do not leave the expanded key in the rk struct > > which got allocated on the stack. > > > > Signed-off-by: Torsten Duwe > > --- > > Another small fix from our FIPS evaluation. I hope you don't mind I merged > > arm32 and arm64 into one patch -- this is really simple. > > --- a/arch/arm/crypto/aes-neonbs-glue.c > > +++ b/arch/arm/crypto/aes-neonbs-glue.c > > @@ -138,6 +138,7 @@ static int aesbs_cbc_setkey(struct crypto_skcipher *tfm, const u8 *in_key, > > kernel_neon_begin(); > > aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds); > > kernel_neon_end(); > > + memzero_explicit(&rk, sizeof(rk)); > > > > return crypto_cipher_setkey(ctx->enc_tfm, in_key, key_len); > > } > > diff --git a/arch/arm64/crypto/aes-neonbs-glue.c b/arch/arm64/crypto/aes-neonbs-glue.c > > index e3e27349a9fe..c0b980503643 100644 > > --- a/arch/arm64/crypto/aes-neonbs-glue.c > > +++ b/arch/arm64/crypto/aes-neonbs-glue.c > > @@ -151,6 +151,7 @@ static int aesbs_cbc_setkey(struct crypto_skcipher *tfm, const u8 *in_key, > > kernel_neon_begin(); > > aesbs_convert_key(ctx->key.rk, rk.key_enc, ctx->key.rounds); > > kernel_neon_end(); > > + memzero_explicit(&rk, sizeof(rk)); > > > > return 0; > > } > > I'm certainly not a crypto person, but this looks sensible to me and I > couldn't find any other similar stack variable usage under > arch/arm64/crypto/ at a quick glance. > > Acked-by: Will Deacon > Acked-by: Ard Biesheuvel