From: Roel Kluin Subject: [PATCH] sha: prevent removal of memset as dead store in sha1_update() Date: Thu, 25 Feb 2010 16:10:27 +0100 Message-ID: <4B8692E3.9030509@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit To: Herbert Xu , Mikael Pettersson , "David S. Miller" , linux-crypto@vger.kernel.org, Andrew Morton Received: from mail-ww0-f46.google.com ([74.125.82.46]:36136 "EHLO mail-ww0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759204Ab0BYPKe (ORCPT ); Thu, 25 Feb 2010 10:10:34 -0500 Sender: linux-crypto-owner@vger.kernel.org List-ID: Due to optimization A call to memset() may be removed as a dead store when the buffer is not used after its value is overwritten. Signed-off-by: Roel Kluin --- see http://cwe.mitre.org/data/slices/2000.html#14 checkpatch.pl, compile and sparse tested. Comments? diff --git a/crypto/sha1_generic.c b/crypto/sha1_generic.c index 0416091..86de0da 100644 --- a/crypto/sha1_generic.c +++ b/crypto/sha1_generic.c @@ -49,8 +49,8 @@ static int sha1_update(struct shash_desc *desc, const u8 *data, src = data; if ((partial + len) > 63) { - u32 temp[SHA_WORKSPACE_WORDS];