From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932653AbeCPCF5 (ORCPT ); Thu, 15 Mar 2018 22:05:57 -0400 Received: from mail-vk0-f66.google.com ([209.85.213.66]:38100 "EHLO mail-vk0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932094AbeCPCFz (ORCPT ); Thu, 15 Mar 2018 22:05:55 -0400 X-Google-Smtp-Source: AG47ELs/UiDYISocBES8nc3Yj6UXPntY63tBsvjraolP48nEG8HSrSInBzYf32cexFx9nn5H8MrfmGrWPtjgNIjNbqw= MIME-Version: 1.0 In-Reply-To: <20180314110834.GB8564@ulmo> References: <20180313162411.GA1983@embeddedgus> <20180314110834.GB8564@ulmo> From: Ben Skeggs Date: Fri, 16 Mar 2018 12:05:53 +1000 Message-ID: Subject: Re: [PATCH v2] drm/nouveau/secboot: remove VLA usage To: Thierry Reding Cc: "Gustavo A. R. Silva" , David Airlie , nouveau@lists.freedesktop.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, David Laight , Ben Skeggs Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 14 March 2018 at 21:08, Thierry Reding wrote: > On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: >> In preparation to enabling -Wvla, remove VLA. In this particular >> case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local >> variable cmdline_size. Also, remove cmdline_size as it is not >> actually useful anymore. >> >> 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 >> --- >> Changes in v2: >> - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change >> is based on the feedback provided by David Laight. Thanks David. >> >> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- >> 1 file changed, 3 insertions(+), 4 deletions(-) > > Reviewed-by: Thierry Reding Thanks everyone. I've taken the patch in my tree. Ben. > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel >