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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A6750C433F5 for ; Fri, 6 May 2022 09:54:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239753AbiEFJ55 (ORCPT ); Fri, 6 May 2022 05:57:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38584 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236473AbiEFJ54 (ORCPT ); Fri, 6 May 2022 05:57:56 -0400 Received: from mga07.intel.com (mga07.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AF28867D28; Fri, 6 May 2022 02:54:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1651830853; x=1683366853; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=D2fOVPqK96/pXvpwlXxzgoBM06E6UgVfGVY77Vl/uHI=; b=GOG57SAghjmheKyF65U2OmRp+KyJ1fnXS9a838VpTSmFys8gqEN9R2ve M0Zkffb4CC/F3U22lUSzFL4BJWrJVwtyTlrEIjUjTx5ySYmCg7n5Gofxi y7ARIkgDWSBbhKc50mZP0gi68RWxpJoZLVstfaDAmY1b8Oxb4+Ms6+48K hBRQry5vTRflHxJKJ5jFtTROP+zjX1a9eQTQe0BVohsCrODlEitm+l5GE fwF7ATFI3RMeTwAjcqMUsX0grdA/yeP/18lgWEb8rfq+ktdXvRo8l87Bm Y47JJNEiaN8ScZzH61KfHa2y8eSP8VqzC5dOfGEzgl5oiw5jWS1Ai7jA2 A==; X-IronPort-AV: E=McAfee;i="6400,9594,10338"; a="331407505" X-IronPort-AV: E=Sophos;i="5.91,203,1647327600"; d="scan'208";a="331407505" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 May 2022 02:54:13 -0700 X-IronPort-AV: E=Sophos;i="5.91,203,1647327600"; d="scan'208";a="621757997" Received: from silpixa00400314.ir.intel.com (HELO silpixa00400314) ([10.237.222.76]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 May 2022 02:54:10 -0700 Date: Fri, 6 May 2022 10:54:07 +0100 From: Giovanni Cabiddu To: Greg KH Cc: herbert@gondor.apana.org.au, linux-crypto@vger.kernel.org, qat-linux@intel.com, vdronov@redhat.com, stable@vger.kernel.org, Adam Guerin , Wojciech Ziemba Subject: Re: [PATCH 10/12] crypto: qat - use memzero_explicit() for algs Message-ID: References: <20220506082327.21605-1-giovanni.cabiddu@intel.com> <20220506082327.21605-11-giovanni.cabiddu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Research and Development Ireland Ltd - Co. Reg. #308263 - Collinstown Industrial Park, Leixlip, County Kildare - Ireland Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On Fri, May 06, 2022 at 11:22:39AM +0200, Greg KH wrote: > On Fri, May 06, 2022 at 09:23:25AM +0100, Giovanni Cabiddu wrote: > > Use memzero_explicit(), instead of a memset(.., 0, ..) in the > > implementation of the algorithms, for buffers containing sensitive > > information to ensure they are wiped out before free. > > > > Cc: stable@vger.kernel.org > > Signed-off-by: Giovanni Cabiddu > > Reviewed-by: Adam Guerin > > Reviewed-by: Wojciech Ziemba > > --- > > drivers/crypto/qat/qat_common/qat_algs.c | 20 +++++++++---------- > > drivers/crypto/qat/qat_common/qat_asym_algs.c | 20 +++++++++---------- > > 2 files changed, 20 insertions(+), 20 deletions(-) > > > > diff --git a/drivers/crypto/qat/qat_common/qat_algs.c b/drivers/crypto/qat/qat_common/qat_algs.c > > index 873533dc43a7..c42df18e02b2 100644 > > --- a/drivers/crypto/qat/qat_common/qat_algs.c > > +++ b/drivers/crypto/qat/qat_common/qat_algs.c > > @@ -637,12 +637,12 @@ static int qat_alg_aead_newkey(struct crypto_aead *tfm, const u8 *key, > > return 0; > > > > out_free_all: > > - memset(ctx->dec_cd, 0, sizeof(struct qat_alg_cd)); > > + memzero_explicit(ctx->dec_cd, sizeof(struct qat_alg_cd)); > > This is for structure fields, why does memset() not work properly here? > The compiler should always call this, it doesn't know what > dma_free_coherent() does. You are referencing this pointer after the > memset() call so all should be working as intended here. > > Because of this, I don't see why this change is needed. Do you have > reports of compilers not calling memset() for all of this properly? Apologies, I had a wrong assumption. Based on a comment in the memzero_explicit() documentation I assumed it should be always used to zero sensitive data. * memzero_explicit - Fill a region of memory (e.g. sensitive * keying data) with 0s. I'm going to drop this patch. Thanks, -- Giovanni