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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C4CFDCD37B9 for ; Sun, 10 May 2026 12:42:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-ID:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=LMy6IKfbJaybzEjnNDkQP/dshg0wQmq9FcR1y+ARCp8=; b=K3bHouzxgW1Gdk /Qg+0agEPKhr5bVCC3v435Gb+LDacQQNoYsfO5p7UiHB7HbqWPJ6tvVHL98VBVio5NcGF7p8aj9WF lG3wYUfT40cVD4nK8k06gb72pA4BzNDIOkngOP7J53ZS99hPU9VyesjH4Cbzzy2aft2AnzGlGZQaG iQOuL0bsZpZRoTyqtJfuFTS9J9gbNJPAbdJkTznJpO24XVzx+01rwmbTAq+P4hlac7GQHmlD0rn4Y doANISjKhP3bgCcj6fSoxUFUl+gMW593nF7cqqisbP3SOh2ysTKYQB35XCsfb4NC2SpOyHUytB5k+ 5Rf9Z+iBmTSfEwIyCgbw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wM3US-0000000AkFj-19iV; Sun, 10 May 2026 12:42:36 +0000 Received: from smtp.forwardemail.net ([121.127.44.73]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1wM3UN-0000000AjtE-1Ikz for linux-rockchip@lists.infradead.org; Sun, 10 May 2026 12:42:32 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kwiboo.se; h=Content-Transfer-Encoding: MIME-Version: References: In-Reply-To: Message-ID: Date: Subject: Cc: To: From; q=dns/txt; s=fe-e1b5cab7be; t=1778416942; bh=zf+CvzCHfezqhJ/7+rm6t/yUbszK6YAKIPYZtb2jbCQ=; b=jQpvcGbg4BejPE533mYUcZ/GWNF3PHn4+hpevscK0vtvl/Y6v1qKRE41A7m2Hvr5CwEqvsbc7 CaagKjHFenJZ10WM9VwXM+dxhbXzdwE0ka8hPUhpMAKNzVxoIcqObe9T7RSl9eB3dIupeK5hJW2 /RpBY+CWk5YOkxKr6rveM+212pVqV+h9G/XYOhf5XD5KsOiJ0I5cmc6STu2dA0Z1ZXIhFjf8mBH rMwl94g+p3j0IklgCxsgztj4y1purffR87aF1QS+9bIuLrOxQKRKnxeJwlwyST1ZNmWRFqMcFto 75zqrI8+/iuBKXiA+zIqyEsIzazL4Rp16VaAFnnVQRKQ== X-Forward-Email-ID: 6a007d0e0d91f03a31a0bc05 X-Forward-Email-Sender: rfc822; jonas@kwiboo.se, smtp.forwardemail.net, 121.127.44.73 X-Forward-Email-Version: 2.8.0 X-Forward-Email-Website: https://forwardemail.net X-Complaints-To: abuse@forwardemail.net X-Report-Abuse: abuse@forwardemail.net X-Report-Abuse-To: abuse@forwardemail.net From: Jonas Karlman To: Andrzej Hajda , Neil Armstrong , Robert Foss , Heiko Stuebner , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Luca Ceresoli , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Simona Vetter Cc: Liu Ying , Sandy Huang , Andy Yan , Chen-Yu Tsai , Christian Hewitt , Diederik de Haas , Nicolas Frattaroli , Dmitry Baryshkov , dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, linux-amlogic@lists.infradead.org, linux-sunxi@lists.linux.dev, imx@lists.linux.dev, linux-kernel@vger.kernel.org Subject: [PATCH v5 07/21] drm: bridge: dw_hdmi: Hold bridge ref until connector cleanup Date: Sun, 10 May 2026 12:40:51 +0000 Message-ID: <20260510124111.1226584-8-jonas@kwiboo.se> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260510124111.1226584-1-jonas@kwiboo.se> References: <20260510124111.1226584-1-jonas@kwiboo.se> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260510_054231_441805_30A4A28B X-CRM114-Status: GOOD ( 11.89 ) X-BeenThere: linux-rockchip@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Upstream kernel work for Rockchip platforms List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-rockchip" Errors-To: linux-rockchip-bounces+linux-rockchip=archiver.kernel.org@lists.infradead.org drmres connector cleanup typically run after devres has released the last dw-hdmi bridge reference. Since struct dw_hdmi, where the connector lives, is freed when the last bridge reference is released, connector cleanup can end up accessing freed memory. Call trace without a bridge reference held until connector cleanup: - dw_hdmi_bridge_detach() - dw_hdmi_bridge_destroy() <<-- struct dw_hdmi is free() - [drm:drm_managed_release] drmres release begin - [drm:drm_managed_release] REL (____ptrval____) drm_mode_config_init_release (0 bytes) - dw_hdmi_connector_destroy() - drm_connector_cleanup() <<-- drm_connector is use-after-free [...] - [drm:drm_managed_release] drmres release end Hold a bridge reference for as long as the connector exists and drop it after drm_connector_cleanup() has completed to keep struct dw_hdmi alive until connector teardown is finished and avoids the use-after-free. Call trace with a bridge reference held until connector cleanup: - dw_hdmi_bridge_detach() - [drm:drm_managed_release] drmres release begin - [drm:drm_managed_release] REL (____ptrval____) drm_mode_config_init_release (0 bytes) - dw_hdmi_connector_destroy() - drm_connector_cleanup() <<-- drm_connector is destroy() - drm_bridge_put() - dw_hdmi_bridge_destroy() <<-- struct dw_hdmi is free() [...] - [drm:drm_managed_release] drmres release end Signed-off-by: Jonas Karlman --- v5: New patch --- drivers/gpu/drm/bridge/synopsys/dw-hdmi.c | 23 ++++++++++++++++++----- 1 file changed, 18 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c index a176eb55418c..cbbd15578042 100644 --- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c +++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c @@ -2528,10 +2528,18 @@ static void dw_hdmi_connector_force(struct drm_connector *connector) mutex_unlock(&hdmi->mutex); } +static void dw_hdmi_connector_destroy(struct drm_connector *connector) +{ + struct dw_hdmi *hdmi = container_of(connector, struct dw_hdmi, connector); + + drm_connector_cleanup(connector); + drm_bridge_put(&hdmi->bridge); +} + static const struct drm_connector_funcs dw_hdmi_connector_funcs = { .fill_modes = drm_helper_probe_single_connector_modes, .detect = dw_hdmi_connector_detect, - .destroy = drm_connector_cleanup, + .destroy = dw_hdmi_connector_destroy, .force = dw_hdmi_connector_force, .reset = drm_atomic_helper_connector_reset, .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, @@ -2548,6 +2556,7 @@ static int dw_hdmi_connector_create(struct dw_hdmi *hdmi) struct drm_connector *connector = &hdmi->connector; struct cec_connector_info conn_info; struct cec_notifier *notifier; + int ret; if (hdmi->version >= 0x200a) connector->ycbcr_420_allowed = @@ -2560,10 +2569,14 @@ static int dw_hdmi_connector_create(struct dw_hdmi *hdmi) drm_connector_helper_add(connector, &dw_hdmi_connector_helper_funcs); - drm_connector_init_with_ddc(hdmi->bridge.dev, connector, - &dw_hdmi_connector_funcs, - DRM_MODE_CONNECTOR_HDMIA, - hdmi->ddc); + ret = drm_connector_init_with_ddc(hdmi->bridge.dev, connector, + &dw_hdmi_connector_funcs, + DRM_MODE_CONNECTOR_HDMIA, + hdmi->ddc); + if (ret) + return ret; + + drm_bridge_get(&hdmi->bridge); /* * drm_connector_attach_max_bpc_property() requires the -- 2.54.0 _______________________________________________ Linux-rockchip mailing list Linux-rockchip@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-rockchip