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 9F485C47095 for ; Wed, 7 Oct 2020 16:01:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 485E621707 for ; Wed, 7 Oct 2020 16:01:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602086500; bh=Ci5si85NH59q4Nd51m/tvgULjrVXrm3GhsTTOHSXt9o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Shd5xIXUXMSmChDAOkaHm14r1YuUrFnrCTzJojNcF/Dwj/hmpBnl/bhJ6SiPiECsY pwV4a/h01i95f1AZFHBgAh0asBnZDwR3psQI7tk0xVkn/zJzT67s43ZTQLSW++YZTJ zXlzp6ciYowAOGGHGpPMjoORoF1igY/JQmis557U= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728948AbgJGQBj (ORCPT ); Wed, 7 Oct 2020 12:01:39 -0400 Received: from mail.kernel.org ([198.145.29.99]:45592 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728289AbgJGQBi (ORCPT ); Wed, 7 Oct 2020 12:01:38 -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 26EE4206E5; Wed, 7 Oct 2020 16:01:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602086498; bh=Ci5si85NH59q4Nd51m/tvgULjrVXrm3GhsTTOHSXt9o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=dr8ZvKeFKU2W8ExkhPUCvGIlh35v3FSxvvSZ1Y31kOFMhvMQP0HT+u32E0VCvZsJx 4WPYtkKulZOo+XCAuXKpNXY3AtCshYHYTrtnanN+US3Cday4znFq+JIdmhLYO5zcI0 FQe+zZ1kD3LAiVajwdLXxeG2YcdKQUDPZSBsoA8E= Date: Wed, 7 Oct 2020 11:07:38 -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 08/14] drm/amd/pm: Replace one-element array with flexible-array in struct phm_cac_leakage_table Message-ID: <0e4dcb96d01f93e3a9288cf8f84548410d0ceee6.1602020074.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_cac_leakage_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->ucNumEntries by sizeof(struct phm_cac_leakage_table) when it should have been multiplied it by sizeof(struct phm_cac_leakage_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/5f7c5d38.iT%2FQTjN+659XUDo5%25lkp@intel.com/ Signed-off-by: Gustavo A. R. Silva --- drivers/gpu/drm/amd/pm/inc/hwmgr.h | 2 +- .../drm/amd/pm/powerplay/hwmgr/processpptables.c | 13 +++++-------- 2 files changed, 6 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/amd/pm/inc/hwmgr.h b/drivers/gpu/drm/amd/pm/inc/hwmgr.h index b8e33325fac6..7e0c948a7097 100644 --- a/drivers/gpu/drm/amd/pm/inc/hwmgr.h +++ b/drivers/gpu/drm/amd/pm/inc/hwmgr.h @@ -393,7 +393,7 @@ union phm_cac_leakage_record { struct phm_cac_leakage_table { uint32_t count; - union phm_cac_leakage_record entries[1]; + union phm_cac_leakage_record entries[]; }; struct phm_samu_clock_voltage_dependency_record { diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c index 7719f52e6d52..e059802d1e25 100644 --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c @@ -1384,17 +1384,14 @@ static int get_cac_leakage_table(struct pp_hwmgr *hwmgr, const ATOM_PPLIB_CAC_Leakage_Table *table) { struct phm_cac_leakage_table *cac_leakage_table; - unsigned long table_size, i; + unsigned long i; - if (hwmgr == NULL || table == NULL || ptable == NULL) + if (!hwmgr || !table || !ptable) return -EINVAL; - table_size = sizeof(ULONG) + - (sizeof(struct phm_cac_leakage_table) * table->ucNumEntries); - - cac_leakage_table = kzalloc(table_size, GFP_KERNEL); - - if (cac_leakage_table == NULL) + cac_leakage_table = kzalloc(struct_size(cac_leakage_table, entries, table->ucNumEntries), + GFP_KERNEL); + if (!cac_leakage_table) return -ENOMEM; cac_leakage_table->count = (ULONG)table->ucNumEntries; -- 2.27.0