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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (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 96A41E9DE6C for ; Thu, 9 Apr 2026 08:48:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id F2BE510E7B7; Thu, 9 Apr 2026 08:48:33 +0000 (UTC) Received: from cstnet.cn (smtp25.cstnet.cn [159.226.251.25]) by gabe.freedesktop.org (Postfix) with ESMTPS id 6F44610E7B7 for ; Thu, 9 Apr 2026 08:48:32 +0000 (UTC) Received: from dfae2b116770.home.arpa (unknown [124.16.138.129]) by APP-05 (Coremail) with SMTP id zQCowADHWQ3SZ9dpAeYJDQ--.43265S2; Thu, 09 Apr 2026 16:48:18 +0800 (CST) From: Wentao Liang To: andrzej.hajda@intel.com, neil.armstrong@linaro.org, rfoss@kernel.org, maarten.lankhorst@linux.intel.com, mripard@kernel.org, tzimmermann@suse.de, airlied@gmail.com, simona@ffwll.ch Cc: Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@gmail.com, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Wentao Liang , stable@vger.kernel.org Subject: [PATCH] drm/bridge: it6505: fix use-after-free in it6505_parse_dt() Date: Thu, 9 Apr 2026 08:48:17 +0000 Message-Id: <20260409084817.470401-1-vulab@iscas.ac.cn> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CM-TRANSID: zQCowADHWQ3SZ9dpAeYJDQ--.43265S2 X-Coremail-Antispam: 1UD129KBjvJXoW7ZryfGFW8tw4fGw4UZF4Utwb_yoW8Xr45pr sIqa1Yvr9rZa9xKay8AryxtF9aya1DXFWrCF9rCw4avwn8X3WUAFW7CrZxXFy8uF1rZw1a yr4vkF9Fgr1Ykr7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9K14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26F1j6w1UM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26F4j 6r4UJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oV Cq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0 I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j6r 4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02628v n2kIc2xKxwCY1x0262kKe7AKxVWUtVW8ZwCY02Avz4vE14v_GFyl42xK82IYc2Ij64vIr4 1l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWUJVWUGwC20s026x8GjcxK 67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r1q6r43MIIYrxkI7VAKI48JMIIF0xvE2Ix0cI 8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j6F4UMIIF0xvE42xK8VAv wI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I0E14 v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUe9NVDUUUU X-Originating-IP: [124.16.138.129] X-CM-SenderInfo: pyxotu46lvutnvoduhdfq/1tbiBgoMA2nXPWqtFQAAsS X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" In it6505_parse_dt(), of_node_put(ep) is called prematurely before the last access to ep when reading the "link-frequencies" property, leading to a use-after-free if the node's reference count drops to zero. Move the of_node_put() calls after the last use of ep in both the success and error paths. Fixes: 380d920b582d ("drm/bridge: add it6505 driver to read data-lanes and link-frequencies from dt") Cc: stable@vger.kernel.org Signed-off-by: Wentao Liang --- drivers/gpu/drm/bridge/ite-it6505.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/ite-it6505.c b/drivers/gpu/drm/bridge/ite-it6505.c index a094803ba7aa..4155b5e67c2d 100644 --- a/drivers/gpu/drm/bridge/ite-it6505.c +++ b/drivers/gpu/drm/bridge/ite-it6505.c @@ -3361,13 +3361,13 @@ static void it6505_parse_dt(struct it6505 *it6505) } ep = of_graph_get_endpoint_by_regs(np, 0, 0); - of_node_put(ep); if (ep) { len = of_property_read_variable_u64_array(ep, "link-frequencies", &link_frequencies, 0, 1); + of_node_put(ep); if (len >= 0) { do_div(link_frequencies, 1000); if (link_frequencies > 297000) { @@ -3382,6 +3382,7 @@ static void it6505_parse_dt(struct it6505 *it6505) *max_dpi_pixel_clock = DPI_PIXEL_CLK_MAX; } } else { + of_node_put(ep); dev_err(dev, "error endpoint, use default"); *max_dpi_pixel_clock = DPI_PIXEL_CLK_MAX; } -- 2.34.1