diff mbox series

[V5,01/20] platform/x86/intel/vsec: Fix xa_alloc memory leak

Message ID 20231123040355.82139-2-david.e.box@linux.intel.com
State New
Headers
Series intel_pmc: Add telemetry API to read counters |

Commit Message

David E. Box Nov. 23, 2023, 4:03 a.m. UTC 
  Fixes memory leak, caught be kmemleak, due to failure to erase auxiliary
device entries from an xarray on removal.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
---
V5 - New patch

 drivers/platform/x86/intel/vsec.c | 24 ++++++++++++++++--------
 drivers/platform/x86/intel/vsec.h |  1 +
 2 files changed, 17 insertions(+), 8 deletions(-)

Comments

Ilpo Järvinen Nov. 23, 2023, 11:27 a.m. UTC | #1 
On Wed, 22 Nov 2023, David E. Box wrote:

> Fixes memory leak, caught be kmemleak, due to failure to erase auxiliary
> device entries from an xarray on removal.
> 
> Signed-off-by: David E. Box <david.e.box@linux.intel.com>

Changelog is quite terse, please improve ;-).

Missing Fixes tag.

> ---
> V5 - New patch
> 
>  drivers/platform/x86/intel/vsec.c | 24 ++++++++++++++++--------
>  drivers/platform/x86/intel/vsec.h |  1 +
>  2 files changed, 17 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/platform/x86/intel/vsec.c b/drivers/platform/x86/intel/vsec.c
> index c1f9e4471b28..ae811bb65910 100644
> --- a/drivers/platform/x86/intel/vsec.c
> +++ b/drivers/platform/x86/intel/vsec.c
> @@ -120,6 +120,8 @@ static void intel_vsec_dev_release(struct device *dev)
>  {
>  	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(dev);
>  
> +	xa_erase(&auxdev_array, intel_vsec_dev->id);
> +
>  	mutex_lock(&vsec_ida_lock);
>  	ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id);
>  	mutex_unlock(&vsec_ida_lock);
> @@ -136,9 +138,21 @@ int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
>  	int ret, id;
>  
>  	mutex_lock(&vsec_ida_lock);
> -	ret = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
> +	id = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
>  	mutex_unlock(&vsec_ida_lock);
> +	if (id < 0) {
> +		kfree(intel_vsec_dev->resource);
> +		kfree(intel_vsec_dev);
> +		return ret;
> +	}
> +
> +	ret = xa_alloc(&auxdev_array, &intel_vsec_dev->id, intel_vsec_dev,
> +		       PMT_XA_LIMIT, GFP_KERNEL);
>  	if (ret < 0) {
> +		mutex_lock(&vsec_ida_lock);
> +		ida_free(intel_vsec_dev->ida, id);
> +		mutex_unlock(&vsec_ida_lock);

Can't order of xa_alloc() and ida_alloc() be reversed such that you don't 
need to do this double mutex dance?
Ilpo Järvinen Nov. 23, 2023, 3:27 p.m. UTC | #2 
On Wed, 22 Nov 2023, David E. Box wrote:

> Fixes memory leak, caught be kmemleak, due to failure to erase auxiliary
> device entries from an xarray on removal.
> 
> Signed-off-by: David E. Box <david.e.box@linux.intel.com>
> ---
> V5 - New patch
> 
>  drivers/platform/x86/intel/vsec.c | 24 ++++++++++++++++--------
>  drivers/platform/x86/intel/vsec.h |  1 +
>  2 files changed, 17 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/platform/x86/intel/vsec.c b/drivers/platform/x86/intel/vsec.c
> index c1f9e4471b28..ae811bb65910 100644
> --- a/drivers/platform/x86/intel/vsec.c
> +++ b/drivers/platform/x86/intel/vsec.c
> @@ -120,6 +120,8 @@ static void intel_vsec_dev_release(struct device *dev)
>  {
>  	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(dev);
>  
> +	xa_erase(&auxdev_array, intel_vsec_dev->id);
> +
>  	mutex_lock(&vsec_ida_lock);
>  	ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id);
>  	mutex_unlock(&vsec_ida_lock);
> @@ -136,9 +138,21 @@ int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
>  	int ret, id;
>  
>  	mutex_lock(&vsec_ida_lock);
> -	ret = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
> +	id = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
>  	mutex_unlock(&vsec_ida_lock);
> +	if (id < 0) {
> +		kfree(intel_vsec_dev->resource);
> +		kfree(intel_vsec_dev);
> +		return ret;
> +	}
> +
> +	ret = xa_alloc(&auxdev_array, &intel_vsec_dev->id, intel_vsec_dev,
> +		       PMT_XA_LIMIT, GFP_KERNEL);
>  	if (ret < 0) {
> +		mutex_lock(&vsec_ida_lock);
> +		ida_free(intel_vsec_dev->ida, id);
> +		mutex_unlock(&vsec_ida_lock);
> +
>  		kfree(intel_vsec_dev->resource);
>  		kfree(intel_vsec_dev);
>  		return ret;
> @@ -147,7 +161,7 @@ int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
>  	if (!parent)
>  		parent = &pdev->dev;
>  
> -	auxdev->id = ret;
> +	auxdev->id = id;
>  	auxdev->name = name;
>  	auxdev->dev.parent = parent;
>  	auxdev->dev.release = intel_vsec_dev_release;
> @@ -169,12 +183,6 @@ int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
>  	if (ret < 0)
>  		return ret;
>  
> -	/* Add auxdev to list */
> -	ret = xa_alloc(&auxdev_array, &id, intel_vsec_dev, PMT_XA_LIMIT,
> -		       GFP_KERNEL);
> -	if (ret)
> -		return ret;
> -
>  	return 0;

BTW, there's also another unnecessary return construct around this which 
remains after this removal. The devm_add_Action_or_reset() value can be 
returned directly (maybe make another patch from that cleanup though 
since this is a Fixes patch).
diff mbox series

Patch

diff --git a/drivers/platform/x86/intel/vsec.c b/drivers/platform/x86/intel/vsec.c
index c1f9e4471b28..ae811bb65910 100644
--- a/drivers/platform/x86/intel/vsec.c
+++ b/drivers/platform/x86/intel/vsec.c
@@ -120,6 +120,8 @@  static void intel_vsec_dev_release(struct device *dev)
 {
 	struct intel_vsec_device *intel_vsec_dev = dev_to_ivdev(dev);
 
+	xa_erase(&auxdev_array, intel_vsec_dev->id);
+
 	mutex_lock(&vsec_ida_lock);
 	ida_free(intel_vsec_dev->ida, intel_vsec_dev->auxdev.id);
 	mutex_unlock(&vsec_ida_lock);
@@ -136,9 +138,21 @@  int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
 	int ret, id;
 
 	mutex_lock(&vsec_ida_lock);
-	ret = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
+	id = ida_alloc(intel_vsec_dev->ida, GFP_KERNEL);
 	mutex_unlock(&vsec_ida_lock);
+	if (id < 0) {
+		kfree(intel_vsec_dev->resource);
+		kfree(intel_vsec_dev);
+		return ret;
+	}
+
+	ret = xa_alloc(&auxdev_array, &intel_vsec_dev->id, intel_vsec_dev,
+		       PMT_XA_LIMIT, GFP_KERNEL);
 	if (ret < 0) {
+		mutex_lock(&vsec_ida_lock);
+		ida_free(intel_vsec_dev->ida, id);
+		mutex_unlock(&vsec_ida_lock);
+
 		kfree(intel_vsec_dev->resource);
 		kfree(intel_vsec_dev);
 		return ret;
@@ -147,7 +161,7 @@  int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
 	if (!parent)
 		parent = &pdev->dev;
 
-	auxdev->id = ret;
+	auxdev->id = id;
 	auxdev->name = name;
 	auxdev->dev.parent = parent;
 	auxdev->dev.release = intel_vsec_dev_release;
@@ -169,12 +183,6 @@  int intel_vsec_add_aux(struct pci_dev *pdev, struct device *parent,
 	if (ret < 0)
 		return ret;
 
-	/* Add auxdev to list */
-	ret = xa_alloc(&auxdev_array, &id, intel_vsec_dev, PMT_XA_LIMIT,
-		       GFP_KERNEL);
-	if (ret)
-		return ret;
-
 	return 0;
 }
 EXPORT_SYMBOL_NS_GPL(intel_vsec_add_aux, INTEL_VSEC);
diff --git a/drivers/platform/x86/intel/vsec.h b/drivers/platform/x86/intel/vsec.h
index 0fd042c171ba..0a6201b4a0e9 100644
--- a/drivers/platform/x86/intel/vsec.h
+++ b/drivers/platform/x86/intel/vsec.h
@@ -45,6 +45,7 @@  struct intel_vsec_device {
 	struct ida *ida;
 	struct intel_vsec_platform_info *info;
 	int num_resources;
+	int id; /* xa */
 	void *priv_data;
 	size_t priv_data_size;
 };