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 99858C433F5 for ; Fri, 6 May 2022 09:22:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1347361AbiEFJ0a (ORCPT ); Fri, 6 May 2022 05:26:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40318 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241303AbiEFJ03 (ORCPT ); Fri, 6 May 2022 05:26:29 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFACD64718; Fri, 6 May 2022 02:22:46 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 5FE42B834B4; Fri, 6 May 2022 09:22:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 80E22C385AA; Fri, 6 May 2022 09:22:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1651828964; bh=vSZ//zBN1YkYsZ0VDmT9OtaFF8zAYa+8GNnMRMqi+tg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=x7F9pJdAyCIHh2KcUIJZ0kjvG2wmcZGDUrXcdlOz0uZmkALAl9KlqUGlDubwIvHRF s7qRDtTk4HHPL7ACI8GmTjAOJgj3O+OlLPw5iC1W49z5aXuZTqnshSBTGo/uRKeDfS lK43A5WMSGzZ+uZN2ekGVc7LQVFk37c0vPamIL1g= Date: Fri, 6 May 2022 11:22:39 +0200 From: Greg KH To: Giovanni Cabiddu 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: <20220506082327.21605-11-giovanni.cabiddu@intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org 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? thanks, greg k-h