[PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[Michal Wilczynski]

Currently rbtn_add() in case of failure is leaking resources. Fix this
by adding a proper rollback. Move devm_kzalloc() before rbtn_acquire(),
so it doesn't require rollback in case of failure. While at it, remove
unnecessary assignment of NULL to device->driver_data and unnecessary
whitespace, plus add a break for the default case in a switch.

Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Fixes: 817a5cdb40c8 ("dell-rbtn: Dell Airplane Mode Switch driver")
Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
---
v2:
 - move devm_kzalloc before rbtn_acquire as suggested

 drivers/platform/x86/dell/dell-rbtn.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/drivers/platform/x86/dell/dell-rbtn.c b/drivers/platform/x86/dell/dell-rbtn.c
index aa0e6c907494..c8fcb537fd65 100644
--- a/drivers/platform/x86/dell/dell-rbtn.c
+++ b/drivers/platform/x86/dell/dell-rbtn.c
@@ -395,16 +395,16 @@ static int rbtn_add(struct acpi_device *device)
 		return -EINVAL;
 	}
 
+	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
+	if (!rbtn_data)
+		return -ENOMEM;
+
 	ret = rbtn_acquire(device, true);
 	if (ret < 0) {
 		dev_err(&device->dev, "Cannot enable device\n");
 		return ret;
 	}
 
-	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
-	if (!rbtn_data)
-		return -ENOMEM;
-
 	rbtn_data->type = type;
 	device->driver_data = rbtn_data;
 
@@ -420,10 +420,12 @@ static int rbtn_add(struct acpi_device *device)
 		break;
 	default:
 		ret = -EINVAL;
+		break;
 	}
+	if (ret)
+		rbtn_acquire(device, false);
 
 	return ret;
-
 }
 
 static void rbtn_remove(struct acpi_device *device)
@@ -442,7 +444,6 @@ static void rbtn_remove(struct acpi_device *device)
 	}
 
 	rbtn_acquire(device, false);
-	device->driver_data = NULL;
 }
 
 static void rbtn_notify(struct acpi_device *device, u32 event)
-- 
2.41.0

Re: [PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[Hans de Goede]

Hi,

On 6/13/23 10:43, Michal Wilczynski wrote:
> Currently rbtn_add() in case of failure is leaking resources. Fix this
> by adding a proper rollback. Move devm_kzalloc() before rbtn_acquire(),
> so it doesn't require rollback in case of failure. While at it, remove
> unnecessary assignment of NULL to device->driver_data and unnecessary
> whitespace, plus add a break for the default case in a switch.
> 
> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Fixes: 817a5cdb40c8 ("dell-rbtn: Dell Airplane Mode Switch driver")
> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Acked-by: Rafael J. Wysocki <rafael@kernel.org>
> ---
> v2:
>  - move devm_kzalloc before rbtn_acquire as suggested


Thank you for your patch, I've applied this patch to my review-hans 
branch:
https://git.kernel.org/pub/scm/linux/kernel/git/pdx86/platform-drivers-x86.git/log/?h=review-hans

Note it will show up in my review-hans branch once I've pushed my
local branch there, which might take a while.

Once I've run some tests on this branch the patches there will be
added to the platform-drivers-x86/for-next branch and eventually
will be included in the pdx86 pull-request to Linus for the next
merge-window.

Regards,

Hans




>  drivers/platform/x86/dell/dell-rbtn.c | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell/dell-rbtn.c b/drivers/platform/x86/dell/dell-rbtn.c
> index aa0e6c907494..c8fcb537fd65 100644
> --- a/drivers/platform/x86/dell/dell-rbtn.c
> +++ b/drivers/platform/x86/dell/dell-rbtn.c
> @@ -395,16 +395,16 @@ static int rbtn_add(struct acpi_device *device)
>  		return -EINVAL;
>  	}
>  
> +	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
> +	if (!rbtn_data)
> +		return -ENOMEM;
> +
>  	ret = rbtn_acquire(device, true);
>  	if (ret < 0) {
>  		dev_err(&device->dev, "Cannot enable device\n");
>  		return ret;
>  	}
>  
> -	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
> -	if (!rbtn_data)
> -		return -ENOMEM;
> -
>  	rbtn_data->type = type;
>  	device->driver_data = rbtn_data;
>  
> @@ -420,10 +420,12 @@ static int rbtn_add(struct acpi_device *device)
>  		break;
>  	default:
>  		ret = -EINVAL;
> +		break;
>  	}
> +	if (ret)
> +		rbtn_acquire(device, false);
>  
>  	return ret;
> -
>  }
>  
>  static void rbtn_remove(struct acpi_device *device)
> @@ -442,7 +444,6 @@ static void rbtn_remove(struct acpi_device *device)
>  	}
>  
>  	rbtn_acquire(device, false);
> -	device->driver_data = NULL;
>  }
>  
>  static void rbtn_notify(struct acpi_device *device, u32 event)

Re: [PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[Andy Shevchenko]

On Tue, Jun 13, 2023 at 11:43:10AM +0300, Michal Wilczynski wrote:
> Currently rbtn_add() in case of failure is leaking resources. Fix this
> by adding a proper rollback. Move devm_kzalloc() before rbtn_acquire(),
> so it doesn't require rollback in case of failure. While at it, remove
> unnecessary assignment of NULL to device->driver_data and unnecessary
> whitespace, plus add a break for the default case in a switch.

> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

Isn't also suggested by Pali?

> Fixes: 817a5cdb40c8 ("dell-rbtn: Dell Airplane Mode Switch driver")
> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Acked-by: Rafael J. Wysocki <rafael@kernel.org>

...

Hans, can it (an additional tag) be folded into applied change?

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[Wilczynski, Michal]

On 6/13/2023 5:12 PM, Andy Shevchenko wrote:
> On Tue, Jun 13, 2023 at 11:43:10AM +0300, Michal Wilczynski wrote:
>> Currently rbtn_add() in case of failure is leaking resources. Fix this
>> by adding a proper rollback. Move devm_kzalloc() before rbtn_acquire(),
>> so it doesn't require rollback in case of failure. While at it, remove
>> unnecessary assignment of NULL to device->driver_data and unnecessary
>> whitespace, plus add a break for the default case in a switch.
>> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Isn't also suggested by Pali?

Oh yeah, should have added a tag for Pali as well

>
>> Fixes: 817a5cdb40c8 ("dell-rbtn: Dell Airplane Mode Switch driver")
>> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
>> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> Acked-by: Rafael J. Wysocki <rafael@kernel.org>
> ...
>
> Hans, can it (an additional tag) be folded into applied change?
>

Re: [PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[Hans de Goede]

Hi,

On 6/13/23 17:12, Andy Shevchenko wrote:
> On Tue, Jun 13, 2023 at 11:43:10AM +0300, Michal Wilczynski wrote:
>> Currently rbtn_add() in case of failure is leaking resources. Fix this
>> by adding a proper rollback. Move devm_kzalloc() before rbtn_acquire(),
>> so it doesn't require rollback in case of failure. While at it, remove
>> unnecessary assignment of NULL to device->driver_data and unnecessary
>> whitespace, plus add a break for the default case in a switch.
> 
>> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> 
> Isn't also suggested by Pali?
> 
>> Fixes: 817a5cdb40c8 ("dell-rbtn: Dell Airplane Mode Switch driver")
>> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
>> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
>> Acked-by: Rafael J. Wysocki <rafael@kernel.org>
> 
> ...
> 
> Hans, can it (an additional tag) be folded into applied change?

Done and pushed to review-hans.

Regards,

Hans

Re: [PATCH v2] platform/x86/dell/dell-rbtn: Fix resources leaking on error path

[Pali Rohár]

On Tuesday 13 June 2023 11:43:10 Michal Wilczynski wrote:
> Currently rbtn_add() in case of failure is leaking resources. Fix this
> by adding a proper rollback. Move devm_kzalloc() before rbtn_acquire(),
> so it doesn't require rollback in case of failure. While at it, remove
> unnecessary assignment of NULL to device->driver_data and unnecessary
> whitespace, plus add a break for the default case in a switch.
> 
> Suggested-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
> Fixes: 817a5cdb40c8 ("dell-rbtn: Dell Airplane Mode Switch driver")
> Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Acked-by: Rafael J. Wysocki <rafael@kernel.org>

Looks good,

Reviewed-by: Pali Rohár <pali@kernel.org>

> ---
> v2:
>  - move devm_kzalloc before rbtn_acquire as suggested
> 
>  drivers/platform/x86/dell/dell-rbtn.c | 13 +++++++------
>  1 file changed, 7 insertions(+), 6 deletions(-)
> 
> diff --git a/drivers/platform/x86/dell/dell-rbtn.c b/drivers/platform/x86/dell/dell-rbtn.c
> index aa0e6c907494..c8fcb537fd65 100644
> --- a/drivers/platform/x86/dell/dell-rbtn.c
> +++ b/drivers/platform/x86/dell/dell-rbtn.c
> @@ -395,16 +395,16 @@ static int rbtn_add(struct acpi_device *device)
>  		return -EINVAL;
>  	}
>  
> +	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
> +	if (!rbtn_data)
> +		return -ENOMEM;
> +
>  	ret = rbtn_acquire(device, true);
>  	if (ret < 0) {
>  		dev_err(&device->dev, "Cannot enable device\n");
>  		return ret;
>  	}
>  
> -	rbtn_data = devm_kzalloc(&device->dev, sizeof(*rbtn_data), GFP_KERNEL);
> -	if (!rbtn_data)
> -		return -ENOMEM;
> -
>  	rbtn_data->type = type;
>  	device->driver_data = rbtn_data;
>  
> @@ -420,10 +420,12 @@ static int rbtn_add(struct acpi_device *device)
>  		break;
>  	default:
>  		ret = -EINVAL;
> +		break;
>  	}
> +	if (ret)
> +		rbtn_acquire(device, false);
>  
>  	return ret;
> -
>  }
>  
>  static void rbtn_remove(struct acpi_device *device)
> @@ -442,7 +444,6 @@ static void rbtn_remove(struct acpi_device *device)
>  	}
>  
>  	rbtn_acquire(device, false);
> -	device->driver_data = NULL;
>  }
>  
>  static void rbtn_notify(struct acpi_device *device, u32 event)
> -- 
> 2.41.0
>