From 9df7b25ab71cee770826d1e7983eb8b6715543d6 Mon Sep 17 00:00:00 2001 From: Jiang Liu Date: Fri, 7 Dec 2012 13:43:50 -0700 Subject: VFIO: unregister IOMMU notifier on error recovery path On error recovery path in function vfio_create_group(), it should unregister the IOMMU notifier for the new VFIO group. Otherwise it may cause invalid memory access later when handling bus notifications. Signed-off-by: Jiang Liu Signed-off-by: Alex Williamson --- drivers/vfio/vfio.c | 31 +++++++++++++++---------------- 1 file changed, 15 insertions(+), 16 deletions(-) diff --git a/drivers/vfio/vfio.c b/drivers/vfio/vfio.c index 56097c6d072d..3b7fa7967221 100644 --- a/drivers/vfio/vfio.c +++ b/drivers/vfio/vfio.c @@ -191,6 +191,17 @@ static void vfio_container_put(struct vfio_container *container) kref_put(&container->kref, vfio_container_release); } +static void vfio_group_unlock_and_free(struct vfio_group *group) +{ + mutex_unlock(&vfio.group_lock); + /* + * Unregister outside of lock. A spurious callback is harmless now + * that the group is no longer in vfio.group_list. + */ + iommu_group_unregister_notifier(group->iommu_group, &group->nb); + kfree(group); +} + /** * Group objects - create, release, get, put, search */ @@ -229,8 +240,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group) minor = vfio_alloc_group_minor(group); if (minor < 0) { - mutex_unlock(&vfio.group_lock); - kfree(group); + vfio_group_unlock_and_free(group); return ERR_PTR(minor); } @@ -239,8 +249,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group) if (tmp->iommu_group == iommu_group) { vfio_group_get(tmp); vfio_free_group_minor(minor); - mutex_unlock(&vfio.group_lock); - kfree(group); + vfio_group_unlock_and_free(group); return tmp; } } @@ -249,8 +258,7 @@ static struct vfio_group *vfio_create_group(struct iommu_group *iommu_group) group, "%d", iommu_group_id(iommu_group)); if (IS_ERR(dev)) { vfio_free_group_minor(minor); - mutex_unlock(&vfio.group_lock); - kfree(group); + vfio_group_unlock_and_free(group); return (struct vfio_group *)dev; /* ERR_PTR */ } @@ -274,16 +282,7 @@ static void vfio_group_release(struct kref *kref) device_destroy(vfio.class, MKDEV(MAJOR(vfio.devt), group->minor)); list_del(&group->vfio_next); vfio_free_group_minor(group->minor); - - mutex_unlock(&vfio.group_lock); - - /* - * Unregister outside of lock. A spurious callback is harmless now - * that the group is no longer in vfio.group_list. - */ - iommu_group_unregister_notifier(group->iommu_group, &group->nb); - - kfree(group); + vfio_group_unlock_and_free(group); } static void vfio_group_put(struct vfio_group *group) -- cgit v1.2.3-59-g8ed1b