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VFIO: unregister IOMMU notifier on error recovery path

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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 <jiang.liu@huawei.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
This commit is contained in:
Jiang Liu 2012-12-07 13:43:50 -07:00 committed by Alex Williamson
parent 2007722a60
commit 9df7b25ab7
1 changed files with 15 additions and 16 deletions
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31
drivers/vfio/vfio.c
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@ -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)