[PATCH] nvme-core: Fixing ctrl de-referencing in nvme_init_ctrl

[Sagi Grimberg]

On 4/3/23 03:41, Irvin Cote wrote:
> Correcting the de-reference count for
> the controller in the core layer to avoid
> a memory leak.

Is this a regression?

> Also cleaning a bit the teardown logic of nvme_init_ctrl.

This is a good cleanup.

> 
> Signed-off-by: Irvin Cote <irvincoteg at gmail.com>
> ---
>   drivers/nvme/host/core.c | 14 ++++++--------
>   1 file changed, 6 insertions(+), 8 deletions(-)
> 
> diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
> index 8698410aeb84..3d7aca7d0f2a 100644
> --- a/drivers/nvme/host/core.c
> +++ b/drivers/nvme/host/core.c
> @@ -5137,14 +5137,12 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
>   	BUILD_BUG_ON(NVME_DSM_MAX_RANGES * sizeof(struct nvme_dsm_range) >
>   			PAGE_SIZE);
>   	ctrl->discard_page = alloc_page(GFP_KERNEL);
> -	if (!ctrl->discard_page) {
> -		ret = -ENOMEM;
> -		goto out;
> -	}
> +	if (!ctrl->discard_page)
> +		return -ENOMEM;
>   
>   	ret = ida_alloc(&nvme_instance_ida, GFP_KERNEL);
>   	if (ret < 0)
> -		goto out;
> +		goto out_free_page;
>   	ctrl->instance = ret;
>   
>   	device_initialize(&ctrl->ctrl_device);
> @@ -5191,10 +5189,10 @@ int nvme_init_ctrl(struct nvme_ctrl *ctrl, struct device *dev,
>   	nvme_put_ctrl(ctrl);
>   	kfree_const(ctrl->device->kobj.name);
>   out_release_instance:
> +	nvme_put_ctrl(ctrl);
>   	ida_free(&nvme_instance_ida, ctrl->instance);
> -out:
> -	if (ctrl->discard_page)
> -		__free_page(ctrl->discard_page);
> +out_free_page:
> +	__free_page(ctrl->discard_page);
>   	return ret;
>   }
>   EXPORT_SYMBOL_GPL(nvme_init_ctrl);