From patchwork Wed May 30 10:17:41 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Carpenter X-Patchwork-Id: 10438397 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 1FFE0602CC for ; Wed, 30 May 2018 10:44:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 07EC12892B for ; Wed, 30 May 2018 10:44:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EF3D02892D; Wed, 30 May 2018 10:44:37 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00, MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,UNPARSEABLE_RELAY autolearn=ham version=3.3.1 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id DD3532892B for ; Wed, 30 May 2018 10:44:36 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3A8A572B43; Wed, 30 May 2018 10:17:59 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from userp2120.oracle.com (userp2120.oracle.com [156.151.31.85]) by gabe.freedesktop.org (Postfix) with ESMTPS id 04AA472B41; Wed, 30 May 2018 10:17:57 +0000 (UTC) Received: from pps.filterd (userp2120.oracle.com [127.0.0.1]) by userp2120.oracle.com (8.16.0.22/8.16.0.22) with SMTP id w4UABuUH188407; Wed, 30 May 2018 10:17:56 GMT Received: from aserv0021.oracle.com (aserv0021.oracle.com [141.146.126.233]) by userp2120.oracle.com with ESMTP id 2j9ev81rrc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 30 May 2018 10:17:56 +0000 Received: from userv0121.oracle.com (userv0121.oracle.com [156.151.31.72]) by aserv0021.oracle.com (8.14.4/8.14.4) with ESMTP id w4UAHsuR012068 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 30 May 2018 10:17:55 GMT Received: from abhmp0002.oracle.com (abhmp0002.oracle.com [141.146.116.8]) by userv0121.oracle.com (8.14.4/8.13.8) with ESMTP id w4UAHs2p013113; Wed, 30 May 2018 10:17:54 GMT Received: from kili.mountain (/197.157.0.20) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 30 May 2018 03:17:53 -0700 Date: Wed, 30 May 2018 13:17:41 +0300 From: Dan Carpenter To: Ben Skeggs Subject: [PATCH] drm/nouveau/core: ERR_PTR vs NULL bug in nvkm_engine_info() Message-ID: <20180530101741.yht7j7zupb6btdvn@kili.mountain> MIME-Version: 1.0 Content-Disposition: inline X-Mailer: git-send-email haha only kidding User-Agent: NeoMutt/20170113 (1.7.2) X-Proofpoint-Virus-Version: vendor=nai engine=5900 definitions=8908 signatures=668702 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 mlxscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1805220000 definitions=main-1805300119 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: David Airlie , nouveau@lists.freedesktop.org, kernel-janitors@vger.kernel.org, dri-devel@lists.freedesktop.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP The nvkm_engine_ref() function returns error pointers, not NULL on error. I fixed that but I also had to reverse some of the checks so it didn't become too convoluted. Fixes: c5c9127b25b2 ("drm/nouveau/device: implement a generic method to query device-specific properties") Signed-off-by: Dan Carpenter diff --git a/drivers/gpu/drm/nouveau/nvkm/core/engine.c b/drivers/gpu/drm/nouveau/nvkm/core/engine.c index d0322ce85172..ee3fbee905e6 100644 --- a/drivers/gpu/drm/nouveau/nvkm/core/engine.c +++ b/drivers/gpu/drm/nouveau/nvkm/core/engine.c @@ -86,14 +86,17 @@ static int nvkm_engine_info(struct nvkm_subdev *subdev, u64 mthd, u64 *data) { struct nvkm_engine *engine = nvkm_engine(subdev); - if (engine->func->info) { - if ((engine = nvkm_engine_ref(engine))) { - int ret = engine->func->info(engine, mthd, data); - nvkm_engine_unref(&engine); - return ret; - } - } - return -ENOSYS; + int ret; + + if (!engine->func->info) + return -ENOSYS; + + engine = nvkm_engine_ref(engine); + if (IS_ERR(engine)) + return PTR_ERR(engine); + ret = engine->func->info(engine, mthd, data); + nvkm_engine_unref(&engine); + return ret; } static int