2022-05-27 08:55:18

by Jianglei Nie

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

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 <[email protected]>
---
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

2022-05-27 12:22:17

by Parav Pandit

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

> From: Paolo Abeni <[email protected]>
> 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 <[email protected]>
> > ---
> > 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:

2022-05-28 19:04:19

by Paolo Abeni

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

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 <[email protected]>
> ---
> 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: