From patchwork Sat Jun 29 12:27:50 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Colin King X-Patchwork-Id: 11023925 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E9F9F138D for ; Sat, 29 Jun 2019 12:27:57 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D2C28287FB for ; Sat, 29 Jun 2019 12:27:57 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C68FC28837; Sat, 29 Jun 2019 12:27:57 +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 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 8ADF228800 for ; Sat, 29 Jun 2019 12:27:57 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 106F86E99D; Sat, 29 Jun 2019 12:27:55 +0000 (UTC) X-Original-To: dri-devel@lists.freedesktop.org Delivered-To: dri-devel@lists.freedesktop.org Received: from youngberry.canonical.com (youngberry.canonical.com [91.189.89.112]) by gabe.freedesktop.org (Postfix) with ESMTPS id 3639C6E99D; Sat, 29 Jun 2019 12:27:54 +0000 (UTC) Received: from 1.general.cking.uk.vpn ([10.172.193.212] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1hhCSM-0005rH-VE; Sat, 29 Jun 2019 12:27:51 +0000 From: Colin King To: Harry Wentland , Leo Li , Alex Deucher , =?utf-8?q?Christian_K=C3=B6nig?= , David Zhou , David Airlie , Daniel Vetter , amd-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org Subject: [PATCH][next] drm/amd/display: don't release dc->current_state if it is null Date: Sat, 29 Jun 2019 13:27:50 +0100 Message-Id: <20190629122750.12219-1-colin.king@canonical.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 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: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" X-Virus-Scanned: ClamAV using ClamSMTP From: Colin Ian King Currently function construct calls destruct if the allocation of dc->current_state fails, however, the destruct function will attempt dereference dc->current_state when calling dc_release_state. Avoid this null pointer dereference by checking if the pointer is not null before calling dc_release_state. Addresses-Coverity: ("Dereference after null check") Signed-off-by: Colin Ian King --- drivers/gpu/drm/amd/display/dc/core/dc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index 18c775a950cc..0e1f132ae310 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -608,8 +608,10 @@ const struct dc_link_settings *dc_link_get_link_cap( static void destruct(struct dc *dc) { - dc_release_state(dc->current_state); - dc->current_state = NULL; + if (dc->current_state) { + dc_release_state(dc->current_state); + dc->current_state = NULL; + } destroy_links(dc);