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=-8.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=ham 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 1330DC5517A for ; Fri, 23 Oct 2020 07:15:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BDB5D2168B for ; Fri, 23 Oct 2020 07:15:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S375651AbgJWHPI (ORCPT ); Fri, 23 Oct 2020 03:15:08 -0400 Received: from verein.lst.de ([213.95.11.211]:55002 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S373936AbgJWHPI (ORCPT ); Fri, 23 Oct 2020 03:15:08 -0400 Received: by verein.lst.de (Postfix, from userid 2407) id 41E1667373; Fri, 23 Oct 2020 09:15:04 +0200 (CEST) Date: Fri, 23 Oct 2020 09:15:03 +0200 From: Christoph Hellwig To: Nick Desaulniers Cc: Andrew Morton , Christoph Hellwig , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] bdi: fix -Wformat-security Message-ID: <20201023071503.GA30563@lst.de> References: <20201023065754.83084-1-nick.desaulniers@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201023065754.83084-1-nick.desaulniers@gmail.com> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 22, 2020 at 11:57:54PM -0700, Nick Desaulniers wrote: > mm/backing-dev.c:810:57: warning: format string is not a string literal > (potentially insecure) [-Wformat-security] > dev = device_create(bdi_class, NULL, MKDEV(0, 0), bdi, bdi->dev_name); The callers never pass format strings here. That being said the fix is probably ok anyway, modulo the obvious style issue. > diff --git a/mm/backing-dev.c b/mm/backing-dev.c > index 408d5051d05b..5755578d671d 100644 > --- a/mm/backing-dev.c > +++ b/mm/backing-dev.c > @@ -807,7 +807,7 @@ int bdi_register_va(struct backing_dev_info *bdi, const char *fmt, va_list args) > return 0; > > vsnprintf(bdi->dev_name, sizeof(bdi->dev_name), fmt, args); > - dev = device_create(bdi_class, NULL, MKDEV(0, 0), bdi, bdi->dev_name); > + dev = device_create(bdi_class, NULL, MKDEV(0, 0), bdi, "%s", bdi->dev_name); Please don't introduce any over 80 char lines.