[PATCH] regulator: Fix memory leak in set_machine_constraints() error paths

[PATCH] regulator: Fix memory leak in set_machine_constraints() error paths

[Axel Lin]

Signed-off-by: Axel Lin <axel.lin@gmail.com>
---
 drivers/regulator/core.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index f59821f..e7655a5 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -787,7 +787,6 @@ static int machine_constraints_voltage(struct regulator_dev *rdev,
 		if (ret < 0) {
 			rdev_err(rdev, "failed to apply %duV constraint\n",
 				 rdev->constraints->min_uV);
-			rdev->constraints = NULL;
 			return ret;
 		}
 	}
@@ -873,7 +872,7 @@ static int machine_constraints_voltage(struct regulator_dev *rdev,
 static int set_machine_constraints(struct regulator_dev *rdev,
 	const struct regulation_constraints *constraints)
 {
-	int ret = 0;
+	int ret;
 	struct regulator_ops *ops = rdev->desc->ops;
 
 	rdev->constraints = kmemdup(constraints, sizeof(*constraints),
@@ -890,7 +889,6 @@ static int set_machine_constraints(struct regulator_dev *rdev,
 		ret = suspend_prepare(rdev, rdev->constraints->initial_state);
 		if (ret < 0) {
 			rdev_err(rdev, "failed to set suspend state\n");
-			rdev->constraints = NULL;
 			goto out;
 		}
 	}
@@ -917,13 +915,15 @@ static int set_machine_constraints(struct regulator_dev *rdev,
 		ret = ops->enable(rdev);
 		if (ret < 0) {
 			rdev_err(rdev, "failed to enable\n");
-			rdev->constraints = NULL;
 			goto out;
 		}
 	}
 
 	print_constraints(rdev);
+	return 0;
 out:
+	kfree(rdev->constraints);
+	rdev->constraints = NULL;
 	return ret;
 }
 
-- 
1.7.4.1

Re: [PATCH] regulator: Fix memory leak in set_machine_constraints() error paths

[Mark Brown]

On Thu, Jul 14, 2011 at 09:29:19PM +0800, Axel Lin wrote:
>  static int set_machine_constraints(struct regulator_dev *rdev,
>  	const struct regulation_constraints *constraints)
>  {
> -	int ret = 0;
> +	int ret;
>  	struct regulator_ops *ops = rdev->desc->ops;
>  

This doesn't look like a leak fix?  There's nothing that checks for
other errors here (like null pointers)?

Re: [PATCH] regulator: Fix memory leak in set_machine_constraints() error paths

[Axel Lin]

2011/7/15 Mark Brown <broonie@opensource.wolfsonmicro.com>:
> On Thu, Jul 14, 2011 at 09:29:19PM +0800, Axel Lin wrote:
>>  static int set_machine_constraints(struct regulator_dev *rdev,
>>       const struct regulation_constraints *constraints)
>>  {
>> -     int ret = 0;
>> +     int ret;
>>       struct regulator_ops *ops = rdev->desc->ops;
>>
>
> This doesn't look like a leak fix?  There's nothing that checks for
> other errors here (like null pointers)?
>

I think it does checking null pointer for rdev->constraints in current
implementation:

static int set_machine_constraints(struct regulator_dev *rdev,
        const struct regulation_constraints *constraints)
{
        int ret;
        struct regulator_ops *ops = rdev->desc->ops;

        rdev->constraints = kmemdup(constraints, sizeof(*constraints),
                                    GFP_KERNEL);
        if (!rdev->constraints)
                return -ENOMEM;


Regards,
Axel

Re: [PATCH] regulator: Fix memory leak in set_machine_constraints() error paths

[Mark Brown]

On Fri, Jul 15, 2011 at 08:44:53AM +0800, Axel Lin wrote:

> I think it does checking null pointer for rdev->constraints in current
> implementation:

So, then does this perhaps open paths where ret might be used
uninitialized?  In general this seems like an unrelated stylistic change
which is unfortunately hard to review from a context diff alone.

Re: [PATCH] regulator: Fix memory leak in set_machine_constraints() error paths

[Axel Lin]

> So, then does this perhaps open paths where ret might be used
> uninitialized?  In general this seems like an unrelated stylistic change
> which is unfortunately hard to review from a context diff alone.
>
I got your point. will send a new version of the patch.

Thanks,
Axel