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 39E5DC47095 for ; Wed, 7 Oct 2020 16:00:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D757D2176B for ; Wed, 7 Oct 2020 16:00:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602086416; bh=l3rN8L44AMXr0k7n8yBVUG4uvWHnJ/3s48bP7J/pDdA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=mnUpZiBwdEBbj1w/3afik6iKLtleM6IJScNUNQWADiVgs7jgz1pb2YVRL8V/vIMxH r5HrWu0fwZdsvTK6qRyi4O0DL/ksbUChtUS+rNeDv54qLtcfCwNgU+habt2eMkdymX 9MY0VLoWRtOyBzgidtsl5jNe9MQxblMP2obk7lRw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728930AbgJGQAP (ORCPT ); Wed, 7 Oct 2020 12:00:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:44854 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727927AbgJGQAP (ORCPT ); Wed, 7 Oct 2020 12:00:15 -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 E79C920789; Wed, 7 Oct 2020 16:00:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1602086414; bh=l3rN8L44AMXr0k7n8yBVUG4uvWHnJ/3s48bP7J/pDdA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=futr1neV1dsv3jHdiLh1vpEzXiG5oXcmHbYybFfRUz0UPxrOsEWnZtrTEchFAHpMt xXypdeA5y1TSOM5hLcbs+4mhkmNkjQn3qbY6ZC3Q9pp7fyUUK1wxlagCkJRjPnPRtT 4G86bvPmwJSjQjD8A3TPfTMGzNm6N6J9rPwdkiKU= Date: Wed, 7 Oct 2020 11:06:14 -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 06/14] drm/amd/pm: Replace one-element array with flexible-array in struct phm_phase_shedding_limits_table Message-ID: 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_phase_shedding_limits_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 ptable->ucNumEntries by sizeof(struct phm_phase_shedding_limits_table) when it should have multiplied it by sizeof(struct phm_phase_shedding_limits_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/5f7c5d36.6PStUZp2HRxAz7IM%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 | 12 ++++-------- 2 files changed, 5 insertions(+), 9 deletions(-) diff --git a/drivers/gpu/drm/amd/pm/inc/hwmgr.h b/drivers/gpu/drm/amd/pm/inc/hwmgr.h index 361cb1125351..ad614e32079e 100644 --- a/drivers/gpu/drm/amd/pm/inc/hwmgr.h +++ b/drivers/gpu/drm/amd/pm/inc/hwmgr.h @@ -161,7 +161,7 @@ struct phm_vce_clock_voltage_dependency_record { struct phm_phase_shedding_limits_table { uint32_t count; - struct phm_phase_shedding_limits_record entries[1]; + struct phm_phase_shedding_limits_record entries[]; }; struct phm_vceclock_voltage_dependency_table { diff --git a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c index a1b198045978..b2ef76580c6a 100644 --- a/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c +++ b/drivers/gpu/drm/amd/pm/powerplay/hwmgr/processpptables.c @@ -1530,16 +1530,12 @@ static int init_phase_shedding_table(struct pp_hwmgr *hwmgr, (((unsigned long)powerplay_table4) + le16_to_cpu(powerplay_table4->usVddcPhaseShedLimitsTableOffset)); struct phm_phase_shedding_limits_table *table; - unsigned long size, i; + unsigned long i; - size = sizeof(unsigned long) + - (sizeof(struct phm_phase_shedding_limits_table) * - ptable->ucNumEntries); - - table = kzalloc(size, GFP_KERNEL); - - if (table == NULL) + table = kzalloc(struct_size(table, entries, ptable->ucNumEntries), + GFP_KERNEL); + if (!table) return -ENOMEM; table->count = (unsigned long)ptable->ucNumEntries; -- 2.27.0