Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752386AbdFHNty (ORCPT ); Thu, 8 Jun 2017 09:49:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:40522 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751816AbdFHNtw (ORCPT ); Thu, 8 Jun 2017 09:49:52 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 2944D8046B Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx04.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=dhowells@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 2944D8046B Organization: Red Hat UK Ltd. Registered Address: Red Hat UK Ltd, Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SI4 1TE, United Kingdom. Registered in England and Wales under Company Registration No. 3798903 Subject: [PATCH 20/23] KEYS: DH: ensure the KDF counter is properly aligned From: David Howells To: jmorris@namei.org Cc: Eric Biggers , Stephan Mueller , linux-kernel@vger.kernel.org, dhowells@redhat.com, linux-security-module@vger.kernel.org, keyrings@vger.kernel.org Date: Thu, 08 Jun 2017 14:49:49 +0100 Message-ID: <149692978940.11452.2775787299367252465.stgit@warthog.procyon.org.uk> In-Reply-To: <149692963884.11452.7673998701432248814.stgit@warthog.procyon.org.uk> References: <149692963884.11452.7673998701432248814.stgit@warthog.procyon.org.uk> User-Agent: StGit/0.17.1-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.28]); Thu, 08 Jun 2017 13:49:52 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1711 Lines: 60 From: Eric Biggers Accessing a 'u8[4]' through a '__be32 *' violates alignment rules. Just make the counter a __be32 instead. Signed-off-by: Eric Biggers Signed-off-by: David Howells Acked-by: Stephan Mueller --- security/keys/dh.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff --git a/security/keys/dh.c b/security/keys/dh.c index 1c1cac677041..63ac87d430db 100644 --- a/security/keys/dh.c +++ b/security/keys/dh.c @@ -130,14 +130,6 @@ static void kdf_dealloc(struct kdf_sdesc *sdesc) kzfree(sdesc); } -/* convert 32 bit integer into its string representation */ -static inline void crypto_kw_cpu_to_be32(u32 val, u8 *buf) -{ - __be32 *a = (__be32 *)buf; - - *a = cpu_to_be32(val); -} - /* * Implementation of the KDF in counter mode according to SP800-108 section 5.1 * as well as SP800-56A section 5.8.1 (Single-step KDF). @@ -154,16 +146,14 @@ static int kdf_ctr(struct kdf_sdesc *sdesc, const u8 *src, unsigned int slen, unsigned int h = crypto_shash_digestsize(desc->tfm); int err = 0; u8 *dst_orig = dst; - u32 i = 1; - u8 iteration[sizeof(u32)]; + __be32 counter = cpu_to_be32(1); while (dlen) { err = crypto_shash_init(desc); if (err) goto err; - crypto_kw_cpu_to_be32(i, iteration); - err = crypto_shash_update(desc, iteration, sizeof(u32)); + err = crypto_shash_update(desc, (u8 *)&counter, sizeof(__be32)); if (err) goto err; @@ -189,7 +179,7 @@ static int kdf_ctr(struct kdf_sdesc *sdesc, const u8 *src, unsigned int slen, dlen -= h; dst += h; - i++; + counter = cpu_to_be32(be32_to_cpu(counter) + 1); } }