Re: [PATCH v2] sdio: Fix a memory leaking bug in wl1271_probe()

Re: [PATCH v2] sdio: Fix a memory leaking bug in wl1271_probe()

[Kalle Valo]

+ linux-wireless

Gen Zhang <blackgod016574@gmail.com> writes:

> In wl1271_probe(), 'glue->core' is allocated by platform_device_alloc(),
> when this allocation fails, ENOMEM is returned. However, 'pdev_data'
> and 'glue' are allocated by devm_kzalloc() before 'glue->core'. When
> platform_device_alloc() returns NULL, we should also free 'pdev_data'
> and 'glue' before wl1271_probe() ends to prevent leaking memory.
>
> Similarly, we should free 'pdev_data' when 'glue' is NULL. And we
> should free 'pdev_data' and 'glue' when 'ret' is error.
>
> Further, we shoulf free 'glue->dev', 'pdev_data' and 'glue' when this
> function normally ends to prevent memory leaking.
>
> Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
> ---
> diff --git a/drivers/net/wireless/ti/wlcore/sdio.c b/drivers/net/wireless/ti/wlcore/sdio.c
> index 4d4b0770..232ce5f 100644
> --- a/drivers/net/wireless/ti/wlcore/sdio.c
> +++ b/drivers/net/wireless/ti/wlcore/sdio.c

You need to CC linux-wireless, otherwise patchwork won't see the patch
and it will not be applied. Also you should use prefix "wlcore:".

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches#commit_title_is_wrong

-- 
Kalle Valo

[PATCH v2] wlcore: sdio: Fix a memory leaking bug in wl1271_probe()

[Gen Zhang]

In wl1271_probe(), 'glue->core' is allocated by platform_device_alloc(),
when this allocation fails, ENOMEM is returned. However, 'pdev_data'
and 'glue' are allocated by devm_kzalloc() before 'glue->core'. When
platform_device_alloc() returns NULL, we should also free 'pdev_data'
and 'glue' before wl1271_probe() ends to prevent leaking memory.

Similarly, we should free 'pdev_data' when 'glue' is NULL. And we
should free 'pdev_data' and 'glue' when 'ret' is error.

Further, we shoulf free 'glue->dev', 'pdev_data' and 'glue' when this
function normally ends to prevent memory leaking.

Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
---
diff --git a/drivers/net/wireless/ti/wlcore/sdio.c b/drivers/net/wireless/ti/wlcore/sdio.c
index 4d4b0770..9110891 100644
--- a/drivers/net/wireless/ti/wlcore/sdio.c
+++ b/drivers/net/wireless/ti/wlcore/sdio.c
@@ -298,8 +298,10 @@ static int wl1271_probe(struct sdio_func *func,
 	pdev_data->if_ops = &sdio_ops;
 
 	glue = devm_kzalloc(&func->dev, sizeof(*glue), GFP_KERNEL);
-	if (!glue)
-		return -ENOMEM;
+	if (!glue) {
+		ret = -ENOMEM;
+		goto out_free1;
+	}
 
 	glue->dev = &func->dev;
 
@@ -311,7 +313,7 @@ static int wl1271_probe(struct sdio_func *func,
 
 	ret = wlcore_probe_of(&func->dev, &irq, &wakeirq, pdev_data);
 	if (ret)
-		goto out;
+		goto out_free2;
 
 	/* if sdio can keep power while host is suspended, enable wow */
 	mmcflags = sdio_get_host_pm_caps(func);
@@ -340,7 +342,7 @@ static int wl1271_probe(struct sdio_func *func,
 	if (!glue->core) {
 		dev_err(glue->dev, "can't allocate platform_device");
 		ret = -ENOMEM;
-		goto out;
+		goto out_free2;
 	}
 
 	glue->core->dev.parent = &func->dev;
@@ -380,12 +382,17 @@ static int wl1271_probe(struct sdio_func *func,
 		dev_err(glue->dev, "can't add platform device\n");
 		goto out_dev_put;
 	}
-	return 0;
+	ret = 0;
 
 out_dev_put:
 	platform_device_put(glue->core);
 
-out:
+out_free2:
+	devm_kfree(&func->dev, glue);
+
+out_free1:
+	devm_kfree(&func->dev, pdev_data);
+
 	return ret;
 }
 
---

Re: [PATCH v2] wlcore: sdio: Fix a memory leaking bug in wl1271_probe()

[Jon Hunter]

On 24/05/2019 03:43, Gen Zhang wrote:
> In wl1271_probe(), 'glue->core' is allocated by platform_device_alloc(),
> when this allocation fails, ENOMEM is returned. However, 'pdev_data'
> and 'glue' are allocated by devm_kzalloc() before 'glue->core'. When
> platform_device_alloc() returns NULL, we should also free 'pdev_data'
> and 'glue' before wl1271_probe() ends to prevent leaking memory.

No, devm_kzalloc() automatically frees memory on failure.

> Similarly, we should free 'pdev_data' when 'glue' is NULL. And we
> should free 'pdev_data' and 'glue' when 'ret' is error.
> 
> Further, we shoulf free 'glue->dev', 'pdev_data' and 'glue' when this
> function normally ends to prevent memory leaking.

Why?

> Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
> ---
> diff --git a/drivers/net/wireless/ti/wlcore/sdio.c b/drivers/net/wireless/ti/wlcore/sdio.c
> index 4d4b0770..9110891 100644
> --- a/drivers/net/wireless/ti/wlcore/sdio.c
> +++ b/drivers/net/wireless/ti/wlcore/sdio.c
> @@ -298,8 +298,10 @@ static int wl1271_probe(struct sdio_func *func,
>  	pdev_data->if_ops = &sdio_ops;
>  
>  	glue = devm_kzalloc(&func->dev, sizeof(*glue), GFP_KERNEL);
> -	if (!glue)
> -		return -ENOMEM;
> +	if (!glue) {
> +		ret = -ENOMEM;
> +		goto out_free1;
> +	}
>  
>  	glue->dev = &func->dev;
>  
> @@ -311,7 +313,7 @@ static int wl1271_probe(struct sdio_func *func,
>  
>  	ret = wlcore_probe_of(&func->dev, &irq, &wakeirq, pdev_data);
>  	if (ret)
> -		goto out;
> +		goto out_free2;
>  
>  	/* if sdio can keep power while host is suspended, enable wow */
>  	mmcflags = sdio_get_host_pm_caps(func);
> @@ -340,7 +342,7 @@ static int wl1271_probe(struct sdio_func *func,
>  	if (!glue->core) {
>  		dev_err(glue->dev, "can't allocate platform_device");
>  		ret = -ENOMEM;
> -		goto out;
> +		goto out_free2;
>  	}
>  
>  	glue->core->dev.parent = &func->dev;
> @@ -380,12 +382,17 @@ static int wl1271_probe(struct sdio_func *func,
>  		dev_err(glue->dev, "can't add platform device\n");
>  		goto out_dev_put;
>  	}
> -	return 0;
> +	ret = 0;

This is completely wrong.

>  out_dev_put:
>  	platform_device_put(glue->core);
>  
> -out:
> +out_free2:
> +	devm_kfree(&func->dev, glue);
> +
> +out_free1:
> +	devm_kfree(&func->dev, pdev_data);
> +
>  	return ret;
>  }
>  
> ---

Jon

-- 
nvpublic