From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933138AbeCMQ7U (ORCPT ); Tue, 13 Mar 2018 12:59:20 -0400 Received: from mail-pf0-f193.google.com ([209.85.192.193]:40368 "EHLO mail-pf0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932671AbeCMQ7R (ORCPT ); Tue, 13 Mar 2018 12:59:17 -0400 X-Google-Smtp-Source: AG47ELtEV5V/KrC26CFhNSOGTJrdHeoHT14Onr+3xt5u6hDj9u7zRA4QfcObjB2l+ksERolvjoP/1w== Date: Tue, 13 Mar 2018 22:29:06 +0530 From: Himanshu Jha To: "Gustavo A. R. Silva" Cc: Jonathan Cameron , Hartmut Knaack , Lars-Peter Clausen , Peter Meerwald-Stadler , linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] iio: potentiometer: ds1803: remove VLA usage Message-ID: <20180313165906.GA11317@himanshu-Vostro-3559> References: <20180313152343.GA31789@embeddedgus> <20180313162454.GA8769@himanshu-Vostro-3559> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Mar 13, 2018 at 11:31:19AM -0500, Gustavo A. R. Silva wrote: > > > On 03/13/2018 11:24 AM, Himanshu Jha wrote: > >Hi Gustavo, > > > >On Tue, Mar 13, 2018 at 10:23:43AM -0500, Gustavo A. R. Silva wrote: > >>In preparation to enabling -Wvla, remove VLA. In this particular > >>case use macro ARRAY_SIZE so the length of array _result_ can be > >>computed at preprocessing time. > >> > >>The use of stack Variable Length Arrays needs to be avoided, as they > >>can be a vector for stack exhaustion, which can be both a runtime bug > >>or a security flaw. Also, in general, as code evolves it is easy to > >>lose track of how big a VLA can get. Thus, we can end up having runtime > >>failures that are hard to debug. > >> > >>Also, fixed as part of the directive to remove all VLAs from > >>the kernel: https://lkml.org/lkml/2018/3/7/621 > >> > >>Signed-off-by: Gustavo A. R. Silva > >>--- > > > >It is already applied as I had sent the patch few days ago. > >https://lkml.org/lkml/2018/3/10/164 > > > >I specifically CC'ed you and Kees to avoid the patch collisions. > > > > I see. Can you please update this spreadsheet: > > https://docs.google.com/spreadsheets/d/1OcfyKK8pJ24esYhSEsW4Q2boZE7UTGbYsSEEtFXf7U0/edit Updated! Also, drivers/iio/humidity/hts221_i2c.c:43:2: warning: ISO C90 forbids variable length array ‘send’ [-Wvla] This was already removed in recent commit when regmap API was used. "6217792 iio: humidity: hts221: add regmap API support" For this I added a short note in the *Notes* column. -- Thanks Himanshu Jha