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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A5E4C433E6 for ; Thu, 27 Aug 2020 22:12:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4A86320848 for ; Thu, 27 Aug 2020 22:12:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727881AbgH0WMC (ORCPT ); Thu, 27 Aug 2020 18:12:02 -0400 Received: from smtprelay0213.hostedemail.com ([216.40.44.213]:35818 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726256AbgH0WMC (ORCPT ); Thu, 27 Aug 2020 18:12:02 -0400 Received: from smtprelay.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by smtpgrave06.hostedemail.com (Postfix) with ESMTP id 854B78123E2F; Thu, 27 Aug 2020 22:12:01 +0000 (UTC) Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay08.hostedemail.com (Postfix) with ESMTP id 74415182CED34; Thu, 27 Aug 2020 22:12:00 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: fly24_1910e5127070 X-Filterd-Recvd-Size: 2747 Received: from XPS-9350.home (unknown [47.151.133.149]) (Authenticated sender: joe@perches.com) by omf16.hostedemail.com (Postfix) with ESMTPA; Thu, 27 Aug 2020 22:11:58 +0000 (UTC) Message-ID: Subject: Re: [Cocci] [PATCH] usb: atm: don't use snprintf() for sysfs attrs From: Joe Perches To: David Laight , Julia Lawall Cc: Alex Dewar , Rasmus Villemoes , cocci , Kees Cook , Greg Kroah-Hartman , "linux-usb@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "Gustavo A. R. Silva" , "accessrunner-general@lists.sourceforge.net" Date: Thu, 27 Aug 2020 15:11:57 -0700 In-Reply-To: References: <20200824222322.22962-1-alex.dewar90@gmail.com> <48f2dc90-7852-eaf1-55d7-2c85cf954688@rasmusvillemoes.dk> <20200827071537.GA168593@kroah.com> <20200827131819.7rcl2f5js3hkoqj2@lenovo-laptop> <20200827144846.yauuttjaqtxaldxg@lenovo-laptop> <5d1dfb9b031130d4d20763ec621233a19d6a88a2.camel@perches.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.36.4-0ubuntu1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2020-08-27 at 22:03 +0000, David Laight wrote: > From: Joe Perches > > Sent: 27 August 2020 21:30 > ... > > Perhaps what's necessary is to find any > > appropriate .show function and change > > any use of strcpy/sprintf within those > > function to some other name. > > > > For instance: > > > > drivers/isdn/mISDN/core.c-static ssize_t name_show(struct device *dev, > > drivers/isdn/mISDN/core.c- struct device_attribute *attr, char *buf) > > drivers/isdn/mISDN/core.c-{ > > drivers/isdn/mISDN/core.c: strcpy(buf, dev_name(dev)); > > drivers/isdn/mISDN/core.c- return strlen(buf); > > drivers/isdn/mISDN/core.c-} > > drivers/isdn/mISDN/core.c-static DEVICE_ATTR_RO(name); > > That form ends up calculating the string length twice. > Better would be: > len = strlen(msg); > memcpy(buf, msg, len); > return len; or given clang's requirement for stpcpy return stpcpy(buf, dev_name(dev)) - buf; (I do not advocate for this ;) 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 X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B0D5EC433E2 for ; Thu, 27 Aug 2020 22:30:14 +0000 (UTC) Received: from isis.lip6.fr (isis.lip6.fr [132.227.60.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2B97B207F7 for ; Thu, 27 Aug 2020 22:30:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2B97B207F7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=perches.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=cocci-bounces@systeme.lip6.fr Received: from systeme.lip6.fr (systeme.lip6.fr [132.227.104.7]) by isis.lip6.fr (8.15.2/8.15.2) with ESMTP id 07RMSON5028886; Fri, 28 Aug 2020 00:28:24 +0200 (CEST) Received: from systeme.lip6.fr (systeme.lip6.fr [127.0.0.1]) by systeme.lip6.fr (Postfix) with ESMTP id 8EA0C4316; Fri, 28 Aug 2020 00:28:24 +0200 (CEST) Received: from osiris.lip6.fr (osiris.lip6.fr [132.227.60.30]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by systeme.lip6.fr (Postfix) with ESMTPS id 317023C97 for ; Fri, 28 Aug 2020 00:28:23 +0200 (CEST) Received: from smtprelay.hostedemail.com (smtprelay0093.hostedemail.com [216.40.44.93]) by osiris.lip6.fr (8.15.2/8.15.2) with ESMTPS id 07RMSKmV027806 (version=TLSv1.2 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO) for ; Fri, 28 Aug 2020 00:28:22 +0200 (CEST) Received: from smtprelay.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by smtpgrave05.hostedemail.com (Postfix) with ESMTP id D7C0F1802F647 for ; Thu, 27 Aug 2020 22:12:03 +0000 (UTC) Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay08.hostedemail.com (Postfix) with ESMTP id 74415182CED34; Thu, 27 Aug 2020 22:12:00 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: fly24_1910e5127070 X-Filterd-Recvd-Size: 2747 Received: from XPS-9350.home (unknown [47.151.133.149]) (Authenticated sender: joe@perches.com) by omf16.hostedemail.com (Postfix) with ESMTPA; Thu, 27 Aug 2020 22:11:58 +0000 (UTC) Message-ID: From: Joe Perches To: David Laight , Julia Lawall Date: Thu, 27 Aug 2020 15:11:57 -0700 In-Reply-To: References: <20200824222322.22962-1-alex.dewar90@gmail.com> <48f2dc90-7852-eaf1-55d7-2c85cf954688@rasmusvillemoes.dk> <20200827071537.GA168593@kroah.com> <20200827131819.7rcl2f5js3hkoqj2@lenovo-laptop> <20200827144846.yauuttjaqtxaldxg@lenovo-laptop> <5d1dfb9b031130d4d20763ec621233a19d6a88a2.camel@perches.com> User-Agent: Evolution 3.36.4-0ubuntu1 MIME-Version: 1.0 X-Greylist: Sender IP whitelisted, Sender e-mail whitelisted, not delayed by milter-greylist-4.4.3 (isis.lip6.fr [132.227.60.2]); Fri, 28 Aug 2020 00:28:24 +0200 (CEST) X-Greylist: Delayed for 04:12:26 by milter-greylist-4.4.3 (osiris.lip6.fr [132.227.60.30]); Fri, 28 Aug 2020 00:28:22 +0200 (CEST) X-Scanned-By: MIMEDefang 2.78 on 132.227.60.2 X-Scanned-By: MIMEDefang 2.78 on 132.227.60.30 Cc: "Gustavo A. R. Silva" , Kees Cook , Greg Kroah-Hartman , "linux-usb@vger.kernel.org" , Rasmus Villemoes , "linux-kernel@vger.kernel.org" , cocci , "accessrunner-general@lists.sourceforge.net" , Alex Dewar Subject: Re: [Cocci] [PATCH] usb: atm: don't use snprintf() for sysfs attrs X-BeenThere: cocci@systeme.lip6.fr X-Mailman-Version: 2.1.13 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: cocci-bounces@systeme.lip6.fr Errors-To: cocci-bounces@systeme.lip6.fr On Thu, 2020-08-27 at 22:03 +0000, David Laight wrote: > From: Joe Perches > > Sent: 27 August 2020 21:30 > ... > > Perhaps what's necessary is to find any > > appropriate .show function and change > > any use of strcpy/sprintf within those > > function to some other name. > > > > For instance: > > > > drivers/isdn/mISDN/core.c-static ssize_t name_show(struct device *dev, > > drivers/isdn/mISDN/core.c- struct device_attribute *attr, char *buf) > > drivers/isdn/mISDN/core.c-{ > > drivers/isdn/mISDN/core.c: strcpy(buf, dev_name(dev)); > > drivers/isdn/mISDN/core.c- return strlen(buf); > > drivers/isdn/mISDN/core.c-} > > drivers/isdn/mISDN/core.c-static DEVICE_ATTR_RO(name); > > That form ends up calculating the string length twice. > Better would be: > len = strlen(msg); > memcpy(buf, msg, len); > return len; or given clang's requirement for stpcpy return stpcpy(buf, dev_name(dev)) - buf; (I do not advocate for this ;) _______________________________________________ Cocci mailing list Cocci@systeme.lip6.fr https://systeme.lip6.fr/mailman/listinfo/cocci