Re: [RFC PATCH 02/24] vhost-vdpa: fix vqs leak in vhost_vdpa_open()

From: Eli Cohen
Date: Thu Sep 24 2020 - 03:48:46 EST


On Thu, Sep 24, 2020 at 11:21:03AM +0800, Jason Wang wrote:
> We need to free vqs during the err path after it has been allocated
> since vhost won't do that for us.
>
> Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
> ---
> drivers/vhost/vdpa.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> index 796fe979f997..9c641274b9f3 100644
> --- a/drivers/vhost/vdpa.c
> +++ b/drivers/vhost/vdpa.c
> @@ -764,6 +764,12 @@ static void vhost_vdpa_free_domain(struct vhost_vdpa *v)
> v->domain = NULL;
> }
>
> +static void vhost_vdpa_cleanup(struct vhost_vdpa *v)
> +{
> + vhost_dev_cleanup(&v->vdev);
> + kfree(v->vdev.vqs);
> +}
> +

Wouldn't it be cleaner to call kfree(vqs) explicilty inside
vhost_vdpa_open() in case of failure and keep the symetry of
vhost_dev_init()/vhost_dev_cleanup()?

> static int vhost_vdpa_open(struct inode *inode, struct file *filep)
> {
> struct vhost_vdpa *v;
> @@ -809,7 +815,7 @@ static int vhost_vdpa_open(struct inode *inode, struct file *filep)
> return 0;
>
> err_init_iotlb:
> - vhost_dev_cleanup(&v->vdev);
> + vhost_vdpa_cleanup(v);
> err:
> atomic_dec(&v->opened);
> return r;
> @@ -840,8 +846,7 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep)
> vhost_vdpa_free_domain(v);
> vhost_vdpa_config_put(v);
> vhost_vdpa_clean_irq(v);
> - vhost_dev_cleanup(&v->vdev);
> - kfree(v->vdev.vqs);
> + vhost_vdpa_cleanup(v);
> mutex_unlock(&d->mutex);
>
> atomic_dec(&v->opened);
> --
> 2.20.1
>