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Message-ID: <tencent_0ED0DF5CD5426F55806D79D028F8A10E490A@qq.com>
From:   Zhang Shurong <zhang_shurong@foxmail.com>
To:     shawnguo@kernel.org
Cc:     s.hauer@pengutronix.de, kernel@pengutronix.de, festevam@gmail.com,
        linux-imx@nxp.com, linux-arm-kernel@lists.infradead.org,
        linux-kernel@vger.kernel.org,
        Zhang Shurong <zhang_shurong@foxmail.com>
Subject: [PATCH] bus: imx-weim: fix to avoid potential NULL pointer dereference
Date:   Sat, 15 Jul 2023 23:21:01 +0800
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

of_match_device() may fail and returns a NULL pointer.

Fix this by checking the return value of of_match_device.

Fixes: 3f98b6baad63 ("drivers: bus: imx-weim: Add support for i.MX1/21/25/27/31/35/50/51/53")
Signed-off-by: Zhang Shurong <zhang_shurong@foxmail.com>
---
 drivers/bus/imx-weim.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/drivers/bus/imx-weim.c b/drivers/bus/imx-weim.c
index 52a5d0447390..65402bb60c18 100644
--- a/drivers/bus/imx-weim.c
+++ b/drivers/bus/imx-weim.c
@@ -202,15 +202,19 @@ static int weim_timing_setup(struct device *dev, struct device_node *np,
 
 static int weim_parse_dt(struct platform_device *pdev)
 {
-	const struct of_device_id *of_id = of_match_device(weim_id_table,
-							   &pdev->dev);
-	const struct imx_weim_devtype *devtype = of_id->data;
+	const struct of_device_id *of_id;
+	const struct imx_weim_devtype *devtype;
 	int ret = 0, have_child = 0;
 	struct device_node *child;
 	struct weim_priv *priv;
 	void __iomem *base;
 	u32 reg;
 
+	of_id = of_match_device(weim_id_table, &pdev->dev);
+	if (!of_id)
+		return -EINVAL;
+
+	devtype = of_id->data;
 	if (devtype == &imx50_weim_devtype) {
 		ret = imx_weim_gpr_setup(pdev);
 		if (ret)
-- 
2.30.2