From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.bootlin.com ([62.4.15.54]:41553 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935676AbeCHJtV (ORCPT ); Thu, 8 Mar 2018 04:49:21 -0500 Date: Thu, 8 Mar 2018 10:49:19 +0100 From: Alexandre Belloni To: "Gustavo A. R. Silva" Cc: Alessandro Zummo , linux-rtc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] rtc: remove VLA usage Message-ID: <20180308094919.GD20370@piout.net> References: <20180308022756.GA28733@embeddedor.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20180308022756.GA28733@embeddedor.com> Sender: linux-rtc-owner@vger.kernel.org List-ID: On 07/03/2018 at 20:27:56 -0600, Gustavo A. R. Silva wrote: > In preparation to enabling -Wvla, remove VLA and replace it > with a fixed-length array instead. > > From a security viewpoint, the use of Variable Length Arrays can be > a vector for stack overflow attacks. Also, in general, as the code > evolves it is easy to lose track of how big a VLA can get. Thus, we > can end up having segfaults 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 > That is a good description, thanks > Signed-off-by: Gustavo A. R. Silva > --- > Changes in v2: > - Update changelog as per Alexandre Belloni request. > - Update the code for rtc-bq32k driver based on Alexandre's feedback. > > drivers/rtc/rtc-bq32k.c | 6 +++++- > drivers/rtc/rtc-mcp795.c | 2 +- > 2 files changed, 6 insertions(+), 2 deletions(-) > Applied. -- Alexandre Belloni, Bootlin (formerly Free Electrons) Embedded Linux and Kernel engineering https://bootlin.com