[PATCH] uio: uio_fsl_elbc_gpcm: Add NULL check in the uio_fsl_elbc_gpcm_probe

[PATCH] uio: uio_fsl_elbc_gpcm: Add NULL check in the uio_fsl_elbc_gpcm_probe

[Henry Martin]

When devm_kasprintf() fails, it returns a NULL pointer. However, this return value is not properly checked in the function uio_fsl_elbc_gpcm_probe.

A NULL check should be added after the devm_kasprintf() to prevent potential NULL pointer dereference error.

Fixes: d57801c45f53e ("uio: uio_fsl_elbc_gpcm: use device-managed allocators")

Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
---
 drivers/uio/uio_fsl_elbc_gpcm.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/uio/uio_fsl_elbc_gpcm.c b/drivers/uio/uio_fsl_elbc_gpcm.c
index 81454c3e2484..59ba1a2dcfe3 100644
--- a/drivers/uio/uio_fsl_elbc_gpcm.c
+++ b/drivers/uio/uio_fsl_elbc_gpcm.c
@@ -384,6 +384,10 @@ static int uio_fsl_elbc_gpcm_probe(struct platform_device *pdev)
 
 	/* set all UIO data */
 	info->mem[0].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn", node);
+	if (!info->mem[0].name) {
+		dev_err(priv->dev, "devm_kasprintf failed for region name\n");
+		return -ENOMEM;
+	}
 	info->mem[0].addr = res.start;
 	info->mem[0].size = resource_size(&res);
 	info->mem[0].memtype = UIO_MEM_PHYS;
-- 
2.34.1

Re: [PATCH] uio: uio_fsl_elbc_gpcm: Add NULL check in the uio_fsl_elbc_gpcm_probe

[Krzysztof Kozlowski]

On 31/03/2025 11:27, Henry Martin wrote:
> When devm_kasprintf() fails, it returns a NULL pointer. However, this return value is not properly checked in the function uio_fsl_elbc_gpcm_probe.
> 
> A NULL check should be added after the devm_kasprintf() to prevent potential NULL pointer dereference error.
> 
> Fixes: d57801c45f53e ("uio: uio_fsl_elbc_gpcm: use device-managed allocators")
> 


Same comments as for other patches.

> Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
> ---
>  drivers/uio/uio_fsl_elbc_gpcm.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/uio/uio_fsl_elbc_gpcm.c b/drivers/uio/uio_fsl_elbc_gpcm.c
> index 81454c3e2484..59ba1a2dcfe3 100644
> --- a/drivers/uio/uio_fsl_elbc_gpcm.c
> +++ b/drivers/uio/uio_fsl_elbc_gpcm.c
> @@ -384,6 +384,10 @@ static int uio_fsl_elbc_gpcm_probe(struct platform_device *pdev)
>  
>  	/* set all UIO data */
>  	info->mem[0].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn", node);
> +	if (!info->mem[0].name) {
> +		dev_err(priv->dev, "devm_kasprintf failed for region name\n");


There is never a printk after memory allocation failure.

Also, just like in some of the other patches, you did not really analyze
the code - you leak here resource map. Just look at the entire code
instead of blindly pasting the same code here and there.

Best regards,
Krzysztof

[PATCH v2] uio: uio_fsl_elbc_gpcm: Add NULL check in the uio_fsl_elbc_gpcm_probe()

[Henry Martin]

devm_kasprintf() returns NULL when memory allocation fails. Currently,
uio_fsl_elbc_gpcm_probe() does not check for this case, which results in
a NULL pointer dereference.

Add NULL check after devm_kasprintf() to prevent this issue and ensuring
no resources are left allocated.

Fixes: d57801c45f53 ("uio: uio_fsl_elbc_gpcm: use device-managed allocators")
Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
---
V1 -> V2: Remove printk after memory failure and add proper resource
cleanup.

 drivers/uio/uio_fsl_elbc_gpcm.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/uio/uio_fsl_elbc_gpcm.c b/drivers/uio/uio_fsl_elbc_gpcm.c
index 81454c3e2484..26be556d956c 100644
--- a/drivers/uio/uio_fsl_elbc_gpcm.c
+++ b/drivers/uio/uio_fsl_elbc_gpcm.c
@@ -384,6 +384,10 @@ static int uio_fsl_elbc_gpcm_probe(struct platform_device *pdev)
 
 	/* set all UIO data */
 	info->mem[0].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn", node);
+	if (!info->mem[0].name) {
+		ret = -ENOMEM;
+		goto out_err3;
+	}
 	info->mem[0].addr = res.start;
 	info->mem[0].size = resource_size(&res);
 	info->mem[0].memtype = UIO_MEM_PHYS;
@@ -423,6 +427,7 @@ static int uio_fsl_elbc_gpcm_probe(struct platform_device *pdev)
 out_err2:
 	if (priv->shutdown)
 		priv->shutdown(info, true);
+out_err3:
 	iounmap(info->mem[0].internal_addr);
 	return ret;
 }
-- 
2.34.1

Re: [PATCH v2] uio: uio_fsl_elbc_gpcm: Add NULL check in the uio_fsl_elbc_gpcm_probe()

[Greg KH]

On Tue, Apr 01, 2025 at 06:02:40PM +0800, Henry Martin wrote:
> devm_kasprintf() returns NULL when memory allocation fails. Currently,
> uio_fsl_elbc_gpcm_probe() does not check for this case, which results in
> a NULL pointer dereference.
> 
> Add NULL check after devm_kasprintf() to prevent this issue and ensuring
> no resources are left allocated.
> 
> Fixes: d57801c45f53 ("uio: uio_fsl_elbc_gpcm: use device-managed allocators")
> Signed-off-by: Henry Martin <bsdhenrymartin@gmail.com>
> ---
> V1 -> V2: Remove printk after memory failure and add proper resource
> cleanup.
> 
>  drivers/uio/uio_fsl_elbc_gpcm.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/uio/uio_fsl_elbc_gpcm.c b/drivers/uio/uio_fsl_elbc_gpcm.c
> index 81454c3e2484..26be556d956c 100644
> --- a/drivers/uio/uio_fsl_elbc_gpcm.c
> +++ b/drivers/uio/uio_fsl_elbc_gpcm.c
> @@ -384,6 +384,10 @@ static int uio_fsl_elbc_gpcm_probe(struct platform_device *pdev)
>  
>  	/* set all UIO data */
>  	info->mem[0].name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%pOFn", node);
> +	if (!info->mem[0].name) {
> +		ret = -ENOMEM;
> +		goto out_err3;
> +	}
>  	info->mem[0].addr = res.start;
>  	info->mem[0].size = resource_size(&res);
>  	info->mem[0].memtype = UIO_MEM_PHYS;
> @@ -423,6 +427,7 @@ static int uio_fsl_elbc_gpcm_probe(struct platform_device *pdev)
>  out_err2:
>  	if (priv->shutdown)
>  		priv->shutdown(info, true);
> +out_err3:
>  	iounmap(info->mem[0].internal_addr);
>  	return ret;
>  }
> -- 
> 2.34.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
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