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

On 27/02/2023 02:41, Kang Chen wrote:
> 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")
> 
No blank lines between tags.

> 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");

No prints for memory allocation errors. Core prints it. Just go to
err_kmalloc.

> +			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;
>  	}
> -

Why? Line break seems nice here.

> +out:
>  	dev_dbg(dev, "Clock type: %d, clock frequency: %d, VSC: %s",
>  		*clock_type, *clock_freq, *fw_vsc_cfg != NULL ? "yes" : "no");
>  }

Best regards,
Krzysztof

From: Kang Chen <void0red@gmail.com>

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>
---
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

Hello:

This patch was applied to netdev/net.git (main)
by Paolo Abeni <pabeni@redhat.com>:

On Mon, 27 Feb 2023 17:30:37 +0800 you wrote:
> From: Kang Chen <void0red@gmail.com>
> 
> 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>
> 
> [...]

Here is the summary with links:
  - [v3] nfc: fdp: add null check of devm_kmalloc_array in fdp_nci_i2c_read_device_properties
    https://git.kernel.org/netdev/net/c/11f180a5d62a

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

On Mon, Feb 27, 2023 at 05:30:37PM +0800, void0red wrote:
> [You don't often get email from void0red@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ]
> 
> From: Kang Chen <void0red@gmail.com>
> 
> 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>

Reviewed-by: Simon Horman <simon.horman@corigine.com>

On 27/02/2023 10:30, void0red wrote:
> From: Kang Chen <void0red@gmail.com>
> 
> 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>
> ---
> v3 -> v2: remove useless prompt and blank lines between tags.


Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof