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=-12.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 40D93C4727F for ; Wed, 7 Oct 2020 16:02:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D4F332173E for ; Wed, 7 Oct 2020 16:02:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602086530; bh=kOWMKdamMcHW4Au2qrv3BhwsErtH4o8/QHcKuDMMRZU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=LyR5hzygJm8hwwX0b/hyHdpXLLecoPPbfZdaalSYskYppgufTj7u7I1I/yui8nHxI 5zplEbwMKw3AxJceB8aOVaO83Xom7THW/EatYCq+RpUtLFzPPgPO7fT4JyFjJQoF4L iZ8lWecGtajMa2SXAqtDXUBy8xf22JibD6DNhZNo= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728968AbgJGQCJ (ORCPT ); Wed, 7 Oct 2020 12:02:09 -0400 Received: from mail.kernel.org ([198.145.29.99]:45850 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728289AbgJGQCJ (ORCPT ); Wed, 7 Oct 2020 12:02:09 -0400 Received: from embeddedor (187-162-31-110.static.axtel.net [187.162.31.110]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 79BDF216C4; Wed, 7 Oct 2020 16:02:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602086528; bh=kOWMKdamMcHW4Au2qrv3BhwsErtH4o8/QHcKuDMMRZU=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=mmGuJcVPJl3uga+8gAEvy+A4ZKDXXdQ1NcKMQBBi5AlUWLanqoW8qlXaryD82NEW4 GoHt/F/tvWyIsctqQoCyH9T9Z5JlH4PeAgiNDx3M7SWbmbHIv3udv5fnnIBt2vPFcy KswO3N14vLrZHi7XvcFESAd5CWm3c3Mw3kLOfJ5M= Date: Wed, 7 Oct 2020 11:08:08 -0500 From: "Gustavo A. R. Silva" To: linux-kernel@vger.kernel.org Cc: linux-hardening@vger.kernel.org, Alex Deucher , Christian =?iso-8859-1?Q?K=F6nig?= , David Airlie , Daniel Vetter , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, "Gustavo A. R. Silva" Subject: [PATCH 09/14] drm/amd/pm: Replace one-element array with flexible-array in struct phm_samu_clock_voltage_dependency_table Message-ID: <7aa857a6242477b90da3643678d2798c7037b30f.1602020074.git.gustavoars@kernel.org> References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. Refactor the code according to the use of a flexible-array member in struct phm_samu_clock_voltage_dependency_table, instead of a one-element array, and use the struct_size() helper to calculate the size for the allocation. Also, save some heap space as the original code is multiplying table->numEntries by sizeof(struct phm_samu_clock_voltage_dependency_table) when it should have been multiplied it by sizeof(struct phm_samu_clock_voltage_dependency_record) instead. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://www.kernel.org/doc/html/v5.9-rc1/process/deprecated.html#zero-length-and-one-element-arrays Build-tested-by: kernel test robot Link: https://lore.kernel.org/lkml/5f7c5d3a.ryM4GmZr3e0JeZy+%25lkp@intel.com/ Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/amd/pm/inc/hwmgr.h | 2 +- .../gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c | 11 ++++------- 2 files changed, 5 insertions(+), 8 deletions(-) diff --git a/drivers/gpu/drm/amd/pm/inc/hwmgr.h b/drivers/gpu/drm/amd/pm/inc/hwmgr.h index 7e0c948a7097..dad703ba0522 100644 --- a/drivers/gpu/drm/amd/pm/inc/hwmgr.h +++ b/drivers/gpu/drm/amd/pm/inc/hwmgr.h @@ -404,7 +404,7 @@ struct phm_samu_clock_voltage_dependency_record { struct phm_samu_clock_voltage_dependency_table { uint8_t count; - struct phm_samu_clock_voltage_dependency_record entries[1]; + struct phm_samu_clock_voltage_dependency_record entries[]; }; struct phm_cac_tdp_table { diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c index e059802d1e25..48d550d26c6a 100644 --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c @@ -1163,15 +1163,12 @@ static int get_samu_clock_voltage_limit_table(struct pp_hwmgr *hwmgr, struct phm_samu_clock_voltage_dependency_table **ptable, const ATOM_PPLIB_SAMClk_Voltage_Limit_Table *table) { - unsigned long table_size, i; + unsigned long i; struct phm_samu_clock_voltage_dependency_table *samu_table; - table_size = sizeof(unsigned long) + - sizeof(struct phm_samu_clock_voltage_dependency_table) * - table->numEntries; - - samu_table = kzalloc(table_size, GFP_KERNEL); - if (NULL == samu_table) + samu_table = kzalloc(struct_size(samu_table, entries, table->numEntries), + GFP_KERNEL); + if (!samu_table) return -ENOMEM; samu_table->count = table->numEntries; -- 2.27.0