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 D63BAC4332F for ; Fri, 4 Nov 2022 09:03:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230507AbiKDJDg (ORCPT ); Fri, 4 Nov 2022 05:03:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34698 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229553AbiKDJDe (ORCPT ); Fri, 4 Nov 2022 05:03:34 -0400 Received: from formenos.hmeau.com (helcar.hmeau.com [216.24.177.18]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 69EFF1AD85; Fri, 4 Nov 2022 02:03:33 -0700 (PDT) Received: from loth.rohan.me.apana.org.au ([192.168.167.2]) by formenos.hmeau.com with smtp (Exim 4.94.2 #2 (Debian)) id 1oqsb9-00A1aS-Jq; Fri, 04 Nov 2022 17:03:25 +0800 Received: by loth.rohan.me.apana.org.au (sSMTP sendmail emulation); Fri, 04 Nov 2022 17:03:24 +0800 Date: Fri, 4 Nov 2022 17:03:24 +0800 From: Herbert Xu To: Kees Cook Cc: Horia =?utf-8?Q?Geant=C4=83?= , Pankaj Gupta , Gaurav Jain , "David S. Miller" , linux-crypto@vger.kernel.org, kernel test robot , linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org Subject: Re: [PATCH] crypto/caam: Avoid GCC constprop bug warning Message-ID: References: <20221028210527.never.934-kees@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20221028210527.never.934-kees@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Oct 28, 2022 at 02:05:31PM -0700, Kees Cook wrote: > > @@ -163,7 +163,7 @@ static inline void append_data(u32 * const desc, const void *data, int len) > { > u32 *offset = desc_end(desc); > > - if (len) /* avoid sparse warning: memcpy with byte count of 0 */ > + if (data && len) /* avoid sparse warning: memcpy with byte count of 0 */ > memcpy(offset, data, len); How about just killing the if clause altogether? I don't see any sparse warnings without it. What am I missing? Cheers, -- Email: Herbert Xu Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt