From patchwork Sun Nov 30 17:03:44 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julia Lawall X-Patchwork-Id: 5408921 X-Patchwork-Delegate: herbert@gondor.apana.org.au Return-Path: X-Original-To: patchwork-linux-crypto@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 5ADCA9F1CD for ; Sun, 30 Nov 2014 17:10:44 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 8CED6201C7 for ; Sun, 30 Nov 2014 17:10:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9F2CD2016C for ; Sun, 30 Nov 2014 17:10:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752766AbaK3RJY (ORCPT ); Sun, 30 Nov 2014 12:09:24 -0500 Received: from mail2-relais-roc.national.inria.fr ([192.134.164.83]:16438 "EHLO mail2-relais-roc.national.inria.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752563AbaK3RJY (ORCPT ); Sun, 30 Nov 2014 12:09:24 -0500 X-IronPort-AV: E=Sophos;i="5.07,488,1413237600"; d="scan'208";a="110322835" Received: from palace.lip6.fr (HELO localhost.localdomain) ([132.227.105.202]) by mail2-relais-roc.national.inria.fr with ESMTP/TLS/DHE-RSA-AES256-SHA; 30 Nov 2014 18:09:17 +0100 From: Julia Lawall To: Herbert Xu Cc: kernel-janitors@vger.kernel.org, "David S. Miller" , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/8 v2] crypto: replace memset by memzero_explicit Date: Sun, 30 Nov 2014 18:03:44 +0100 Message-Id: <1417367029-32762-4-git-send-email-Julia.Lawall@lip6.fr> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1417367029-32762-1-git-send-email-Julia.Lawall@lip6.fr> References: <1417367029-32762-1-git-send-email-Julia.Lawall@lip6.fr> Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Julia Lawall Memset on a local variable may be removed when it is called just before the variable goes out of scope. Using memzero_explicit defeats this optimization. A simplified version of the semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // @@ identifier x; type T; @@ { ... when any T x[...]; ... when any when exists - memset + memzero_explicit (x, -0, ...) ... when != x when strict } // This change was suggested by Daniel Borkmann Signed-off-by: Julia Lawall --- Daniel Borkmann suggested that these patches could go through Herbert Xu's cryptodev tree. v2: fixed email address arch/x86/crypto/sha256_ssse3_glue.c | 2 +- arch/x86/crypto/sha512_ssse3_glue.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/arch/x86/crypto/sha512_ssse3_glue.c b/arch/x86/crypto/sha512_ssse3_glue.c index 26a5898..0b6af26 100644 --- a/arch/x86/crypto/sha512_ssse3_glue.c +++ b/arch/x86/crypto/sha512_ssse3_glue.c @@ -219,7 +219,7 @@ static int sha384_ssse3_final(struct shash_desc *desc, u8 *hash) sha512_ssse3_final(desc, D); memcpy(hash, D, SHA384_DIGEST_SIZE); - memset(D, 0, SHA512_DIGEST_SIZE); + memzero_explicit(D, SHA512_DIGEST_SIZE); return 0; } diff --git a/arch/x86/crypto/sha256_ssse3_glue.c b/arch/x86/crypto/sha256_ssse3_glue.c index 4dc100d..8fad72f 100644 --- a/arch/x86/crypto/sha256_ssse3_glue.c +++ b/arch/x86/crypto/sha256_ssse3_glue.c @@ -211,7 +211,7 @@ static int sha224_ssse3_final(struct shash_desc *desc, u8 *hash) sha256_ssse3_final(desc, D); memcpy(hash, D, SHA224_DIGEST_SIZE); - memset(D, 0, SHA256_DIGEST_SIZE); + memzero_explicit(D, SHA256_DIGEST_SIZE); return 0; }