From:   Kang Chen <void0red@gmail.com>
To:     simon.horman@corigine.com
Cc:     krzysztof.kozlowski@linaro.org, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, void0red@gmail.com
Subject: [PATCH v2] nfc: fdp: add null check of devm_kmalloc_array in fdp_nci_i2c_read_device_properties
Date:   Mon, 27 Feb 2023 09:41:44 +0800
Message-Id: <20230227014144.1466102-1-void0red@gmail.com>
In-Reply-To: <Y/t729AIYjxuP6X6@corigine.com>
References: <Y/t729AIYjxuP6X6@corigine.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

devm_kmalloc_array may fails, *fw_vsc_cfg might be null and cause
out-of-bounds write in device_property_read_u8_array later.

Fixes: a06347c04c13 ("NFC: Add Intel Fields Peak NFC solution driver")

Signed-off-by: Kang Chen <void0red@gmail.com>
---
v2 -> v1: add debug prompt and Fixes tag

 drivers/nfc/fdp/i2c.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/nfc/fdp/i2c.c b/drivers/nfc/fdp/i2c.c
index 2d53e0f88..d3272a54b 100644
--- a/drivers/nfc/fdp/i2c.c
+++ b/drivers/nfc/fdp/i2c.c
@@ -247,6 +247,11 @@ static void fdp_nci_i2c_read_device_properties(struct device *dev,
 					   len, sizeof(**fw_vsc_cfg),
 					   GFP_KERNEL);
 
+		if (!*fw_vsc_cfg) {
+			dev_dbg(dev, "Not enough memory\n");
+			goto out;
+		}
+
 		r = device_property_read_u8_array(dev, FDP_DP_FW_VSC_CFG_NAME,
 						  *fw_vsc_cfg, len);
 
@@ -259,7 +264,7 @@ static void fdp_nci_i2c_read_device_properties(struct device *dev,
 		dev_dbg(dev, "FW vendor specific commands not present\n");
 		*fw_vsc_cfg = NULL;
 	}
-
+out:
 	dev_dbg(dev, "Clock type: %d, clock frequency: %d, VSC: %s",
 		*clock_type, *clock_freq, *fw_vsc_cfg != NULL ? "yes" : "no");
 }
-- 
2.34.1