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=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham 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 5A2A6C43142 for ; Tue, 31 Jul 2018 01:05:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 07C79208A3 for ; Tue, 31 Jul 2018 01:05:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 07C79208A3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732009AbeGaCnG (ORCPT ); Mon, 30 Jul 2018 22:43:06 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:56320 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1728705AbeGaCnF (ORCPT ); Mon, 30 Jul 2018 22:43:05 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 3CFB77C6A9; Tue, 31 Jul 2018 01:05:26 +0000 (UTC) Received: from malachite.bss.redhat.com (dhcp-10-20-1-11.bss.redhat.com [10.20.1.11]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3CE8F112D199; Tue, 31 Jul 2018 01:05:24 +0000 (UTC) From: Lyude Paul To: nouveau@lists.freedesktop.org Cc: Karol Herbst , Ben Skeggs , David Airlie , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH v2] drm/nouveau: Fix potential memory access error in nouveau_debugfs_pstate_get() Date: Mon, 30 Jul 2018 21:05:23 -0400 Message-Id: <20180731010523.22388-1-lyude@redhat.com> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Tue, 31 Jul 2018 01:05:26 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.2]); Tue, 31 Jul 2018 01:05:26 +0000 (UTC) for IP:'10.11.54.3' DOMAIN:'int-mx03.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'lyude@redhat.com' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org nouveau_debugfs(drm) will never be NULL, because we're taking the value of the potentially null device pointer and adding to it so it isn't 0x0. So, check if drm is NULL instead. Signed-off-by: Lyude Paul Cc: Karol Herbst --- Forgot to hit :w before committing, whoops! drivers/gpu/drm/nouveau/nouveau_debugfs.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_debugfs.c b/drivers/gpu/drm/nouveau/nouveau_debugfs.c index 963a4dba8213..8e758c4cb4fd 100644 --- a/drivers/gpu/drm/nouveau/nouveau_debugfs.c +++ b/drivers/gpu/drm/nouveau/nouveau_debugfs.c @@ -50,13 +50,15 @@ static int nouveau_debugfs_pstate_get(struct seq_file *m, void *data) { struct drm_device *drm = m->private; - struct nouveau_debugfs *debugfs = nouveau_debugfs(drm); - struct nvif_object *ctrl = &debugfs->ctrl; + struct nouveau_debugfs *debugfs; + struct nvif_object *ctrl; struct nvif_control_pstate_info_v0 info = {}; int ret, i; - if (!debugfs) + if (!drm) return -ENODEV; + debugfs = nouveau_debugfs(drm); + ctrl = &debugfs->ctrl; ret = nvif_mthd(ctrl, NVIF_CONTROL_PSTATE_INFO, &info, sizeof(info)); if (ret) -- 2.17.1