Re: [PATCH 1/2] vfio: platform: Fix reset module leak in error path

From: Auger Eric
Date: Wed Feb 14 2018 - 03:37:08 EST


Hi Geert,

On 13/02/18 17:36, Geert Uytterhoeven wrote:
> If the IOMMU group setup fails, the reset module is not released.
>
> Fixes: b5add544d677d363 ("vfio, platform: make reset driver a requirement by default")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
> ---
> drivers/vfio/platform/vfio_platform_common.c | 15 ++++++++++-----
> 1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
> index 35469af87f88678e..b60bb5326668498c 100644
> --- a/drivers/vfio/platform/vfio_platform_common.c
> +++ b/drivers/vfio/platform/vfio_platform_common.c
> @@ -680,18 +680,23 @@ int vfio_platform_probe_common(struct vfio_platform_device *vdev,

Thanks for fixing this.

If I am not wrong we also leak the reset_module if
vfio_platform_get_reset() fails to find the reset function (of_reset ==
NULL), in which case we should do the module_put() in
vfio_platform_get_reset().

Thanks

Eric
> group = vfio_iommu_group_get(dev);
> if (!group) {
> pr_err("VFIO: No IOMMU group for device %s\n", vdev->name);
> - return -EINVAL;
> + ret = -EINVAL;
> + goto put_reset;
> }
>
> ret = vfio_add_group_dev(dev, &vfio_platform_ops, vdev);
> - if (ret) {
> - vfio_iommu_group_put(group, dev);
> - return ret;
> - }
> + if (ret)
> + goto put_iommu;
>
> mutex_init(&vdev->igate);
>
> return 0;
> +
> +put_iommu:
> + vfio_iommu_group_put(group, dev);
> +put_reset:
> + vfio_platform_put_reset(vdev);
> + return ret;
> }
> EXPORT_SYMBOL_GPL(vfio_platform_probe_common);
>
>