Subject: [PATCH v3] nfc: fdp: add null check of devm_kmalloc_array in fdp_nci_i2c_read_device_properties

From: void0red <[email-masked]>
Date: Mon, 27 Feb 2023 17:30:37 +0800

From: Kang Chen <[email-masked]>

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 <[email-masked]>
---
v3 -> v2: remove useless prompt and blank lines between tags.
v2 -> v1: add debug prompt and Fixes tag

 drivers/nfc/fdp/i2c.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/nfc/fdp/i2c.c b/drivers/nfc/fdp/i2c.c
index 2d53e0f88..1e0f2297f 100644
--- a/drivers/nfc/fdp/i2c.c
+++ b/drivers/nfc/fdp/i2c.c
@@ -247,6 +247,9 @@ static void fdp_nci_i2c_read_device_properties(struct device *dev,
 					   len, sizeof(**fw_vsc_cfg),
 					   GFP_KERNEL);
 
+		if (!*fw_vsc_cfg)
+			goto alloc_err;
+
 		r = device_property_read_u8_array(dev, FDP_DP_FW_VSC_CFG_NAME,
 						  *fw_vsc_cfg, len);
 
@@ -260,6 +263,7 @@ static void fdp_nci_i2c_read_device_properties(struct device *dev,
 		*fw_vsc_cfg = NULL;
 	}
 
+alloc_err:
 	dev_dbg(dev, "Clock type: %d, clock frequency: %d, VSC: %s",
 		*clock_type, *clock_freq, *fw_vsc_cfg != NULL ? "yes" : "no");
 }
-- 
2.34.1