net/mlx5: Fix memory leak in mlx5_sf_dev_add()

[PATCH] net/mlx5: Fix memory leak in mlx5_sf_dev_add()

Posted by Jianglei Nie 3 years, 11 months ago

The variable id is allocated by mlx5_adev_idx_alloc(). When some error
happens, the id should be freed by mlx5_adev_idx_free().But when
auxiliary_device_add() and xa_insert() fail, the id is not freed,which
will lead to a potential memory leak.

We can fix it by calling mlx5_sf_dev_add() when auxiliary_device_add()
and xa_insert() fail.

Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
---
 drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
index 7da012ff0d41..9f222061a1c0 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
@@ -125,13 +125,16 @@ static void mlx5_sf_dev_add(struct mlx5_core_dev *dev, u16 sf_index, u16 fn_id,
 
 	err = auxiliary_device_add(&sf_dev->adev);
 	if (err) {
+		mlx5_adev_idx_free(id);
 		put_device(&sf_dev->adev.dev);
 		goto add_err;
 	}
 
 	err = xa_insert(&table->devices, sf_index, sf_dev, GFP_KERNEL);
-	if (err)
+	if (err) {
+		mlx5_adev_idx_free(id);
 		goto xa_err;
+	}
 	return;
 
 xa_err:
-- 
2.25.1

Re: [PATCH] net/mlx5: Fix memory leak in mlx5_sf_dev_add()

Posted by Paolo Abeni 3 years, 11 months ago

On Thu, 2022-05-26 at 16:44 +0800, Jianglei Nie wrote:
> The variable id is allocated by mlx5_adev_idx_alloc(). When some error
> happens, the id should be freed by mlx5_adev_idx_free().But when
> auxiliary_device_add() and xa_insert() fail, the id is not freed,which
> will lead to a potential memory leak.
> 
> We can fix it by calling mlx5_sf_dev_add() when auxiliary_device_add()
> and xa_insert() fail.
> 
> Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> index 7da012ff0d41..9f222061a1c0 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> @@ -125,13 +125,16 @@ static void mlx5_sf_dev_add(struct mlx5_core_dev *dev, u16 sf_index, u16 fn_id,
>  
>  	err = auxiliary_device_add(&sf_dev->adev);
>  	if (err) {
> +		mlx5_adev_idx_free(id);
>  		put_device(&sf_dev->adev.dev);

This looks not correct. put_device() -> mlx5_sf_dev_release() -> should
already take care of that.

>  		goto add_err;
>  	}
>  
>  	err = xa_insert(&table->devices, sf_index, sf_dev, GFP_KERNEL);
> -	if (err)
> +	if (err) {
> +		mlx5_adev_idx_free(id);
>  		goto xa_err;
> +	}
>  	return;
>  
>  xa_err:

RE: [PATCH] net/mlx5: Fix memory leak in mlx5_sf_dev_add()

Posted by Parav Pandit 3 years, 11 months ago


> From: Paolo Abeni <pabeni@redhat.com>
> Sent: Thursday, May 26, 2022 7:14 AM
> 
> On Thu, 2022-05-26 at 16:44 +0800, Jianglei Nie wrote:
> > The variable id is allocated by mlx5_adev_idx_alloc(). When some error
> > happens, the id should be freed by mlx5_adev_idx_free().But when
> > auxiliary_device_add() and xa_insert() fail, the id is not freed,which
> > will lead to a potential memory leak.
> >
> > We can fix it by calling mlx5_sf_dev_add() when auxiliary_device_add()
> > and xa_insert() fail.
> >
> > Signed-off-by: Jianglei Nie <niejianglei2021@163.com>
> > ---
> >  drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c | 5 ++++-
> >  1 file changed, 4 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> > b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> > index 7da012ff0d41..9f222061a1c0 100644
> > --- a/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> > +++ b/drivers/net/ethernet/mellanox/mlx5/core/sf/dev/dev.c
> > @@ -125,13 +125,16 @@ static void mlx5_sf_dev_add(struct
> mlx5_core_dev
> > *dev, u16 sf_index, u16 fn_id,
> >
> >  	err = auxiliary_device_add(&sf_dev->adev);
> >  	if (err) {
> > +		mlx5_adev_idx_free(id);
> >  		put_device(&sf_dev->adev.dev);
> 
> This looks not correct. put_device() -> mlx5_sf_dev_release() -> should
> already take care of that.
> 
Right. As Paolo explained, current code doesn’t have the cited bug.

> >  		goto add_err;
> >  	}
> >
> >  	err = xa_insert(&table->devices, sf_index, sf_dev, GFP_KERNEL);
> > -	if (err)
> > +	if (err) {
> > +		mlx5_adev_idx_free(id);
> >  		goto xa_err;
> > +	}
> >  	return;
> >
> >  xa_err: