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=-8.6 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,USER_AGENT_SANE_1 autolearn=ham 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 189E2C1975A for ; Tue, 17 Mar 2020 22:17:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CAD2420738 for ; Tue, 17 Mar 2020 22:17:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584483469; bh=sY4cOhcMEMawFpaLftRkDuoAZYkzfT6Iq/pDMIVQ+QM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Jk+0lnghDvfjl/nzGxFx7ENJQghzkFCHI5GRJEmdpQ43dsTncmYvVN+NQQdadLUwY PZOqApoi+6X1vveodqQQzYlhojNzCeQ1gP09LrzfTeP10NK0V/Gi1nx9kdmPVY0Hla vJseENEtMdKQQ5vG+bG/wmDIDWQzyELs3E6mZNDo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726549AbgCQWRt (ORCPT ); Tue, 17 Mar 2020 18:17:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:33490 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726476AbgCQWRt (ORCPT ); Tue, 17 Mar 2020 18:17:49 -0400 Received: from willie-the-truck (236.31.169.217.in-addr.arpa [217.169.31.236]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 15A73206EC; Tue, 17 Mar 2020 22:17:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584483468; bh=sY4cOhcMEMawFpaLftRkDuoAZYkzfT6Iq/pDMIVQ+QM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=0QGP7zI9fM58OdTLqDxjLIcR2NDM+WwQ4MBisE/1SCYXBDjdNnC+PTF/305E5GyST kIqZVvbLlzYcUqBHggnCaCPlwSH7VtJqmiU8YuCYpkjEJG1LvNZnpjOCI11ZdmF4Ey 0175SzJkfPb8KuTVROY2dRPony8hRwWy9EPhI0ys= Date: Tue, 17 Mar 2020 22:17:43 +0000 From: Will Deacon To: Torsten Duwe Cc: Catalin Marinas , Herbert Xu , "David S. Miller" , Russell King , linux-crypto@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, ardb@kernel.org Subject: Re: [Patch][Fix] crypto: arm{,64} neon: memzero_explicit aes-cbc key Message-ID: <20200317221743.GD20788@willie-the-truck> References: <20200313110258.94A0668C4E@verein.lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200313110258.94A0668C4E@verein.lst.de> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org [+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 Will