From patchwork Sat Mar 27 11:57:40 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Cercueil X-Patchwork-Id: 410788 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=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 229FBC433E0 for ; Sat, 27 Mar 2021 11:58:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EB4CB6197C for ; Sat, 27 Mar 2021 11:58:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231577AbhC0L6H (ORCPT ); Sat, 27 Mar 2021 07:58:07 -0400 Received: from aposti.net ([89.234.176.197]:58558 "EHLO aposti.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230322AbhC0L6G (ORCPT ); Sat, 27 Mar 2021 07:58:06 -0400 From: Paul Cercueil To: Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart Cc: Sam Ravnborg , David Airlie , Daniel Vetter , od@zcrc.me, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, Paul Cercueil , stable@vger.kernel.org, Jonas Karlman , Jernej Skrabec , Laurent Pinchart Subject: [PATCH v4 1/3] drm: bridge/panel: Cleanup connector on bridge detach Date: Sat, 27 Mar 2021 11:57:40 +0000 Message-Id: <20210327115742.18986-2-paul@crapouillou.net> In-Reply-To: <20210327115742.18986-1-paul@crapouillou.net> References: <20210327115742.18986-1-paul@crapouillou.net> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org If we don't call drm_connector_cleanup() manually in panel_bridge_detach(), the connector will be cleaned up with the other DRM objects in the call to drm_mode_config_cleanup(). However, since our drm_connector is devm-allocated, by the time drm_mode_config_cleanup() will be called, our connector will be long gone. Therefore, the connector must be cleaned up when the bridge is detached to avoid use-after-free conditions. v2: Cleanup connector only if it was created v3: Add FIXME v4: (Use connector->dev) directly in if() block Fixes: 13dfc0540a57 ("drm/bridge: Refactor out the panel wrapper from the lvds-encoder bridge.") Cc: # 4.12+ Cc: Andrzej Hajda Cc: Neil Armstrong Cc: Laurent Pinchart Cc: Jonas Karlman Cc: Jernej Skrabec Signed-off-by: Paul Cercueil Reviewed-by: Laurent Pinchart --- drivers/gpu/drm/bridge/panel.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/gpu/drm/bridge/panel.c b/drivers/gpu/drm/bridge/panel.c index 0ddc37551194..c916f4b8907e 100644 --- a/drivers/gpu/drm/bridge/panel.c +++ b/drivers/gpu/drm/bridge/panel.c @@ -87,6 +87,18 @@ static int panel_bridge_attach(struct drm_bridge *bridge, static void panel_bridge_detach(struct drm_bridge *bridge) { + struct panel_bridge *panel_bridge = drm_bridge_to_panel_bridge(bridge); + struct drm_connector *connector = &panel_bridge->connector; + + /* + * Cleanup the connector if we know it was initialized. + * + * FIXME: This wouldn't be needed if the panel_bridge structure was + * allocated with drmm_kzalloc(). This might be tricky since the + * drm_device pointer can only be retrieved when the bridge is attached. + */ + if (connector->dev) + drm_connector_cleanup(connector); } static void panel_bridge_pre_enable(struct drm_bridge *bridge)