[PATCH 5.5 302/367] virtio_balloon: Fix memory leaks on errors in virtballoon_probe()

Greg Kroah-Hartman
2020-02-10T12:55:58Z

From: David Hildenbrand <david@redhat.com>

commit 1ad6f58ea9364b0a5d8ae06249653ac9304a8578 upstream.

We forget to put the inode and unmount the kernfs used for compaction.

Fixes: 71994620bb25 ("virtio_balloon: replace oom notifier with shrinker")
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Wei Wang <wei.w.wang@intel.com>
Cc: Liang Li <liang.z.li@intel.com>
Signed-off-by: David Hildenbrand <david@redhat.com>
Link: https://lore.kernel.org/r/20200205163402.42627-3-david@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/virtio/virtio_balloon.c | 13 +++++++++----
1 file changed, 9 insertions(+), 4 deletions(-)

--- a/drivers/virtio/virtio_balloon.c
+++ b/drivers/virtio/virtio_balloon.c
@@ -901,8 +901,7 @@ static int virtballoon_probe(struct virt
vb->vb_dev_info.inode = alloc_anon_inode(balloon_mnt->mnt_sb);
if (IS_ERR(vb->vb_dev_info.inode)) {
err = PTR_ERR(vb->vb_dev_info.inode);
- kern_unmount(balloon_mnt);
- goto out_del_vqs;
+ goto out_kern_unmount;
}
vb->vb_dev_info.inode->i_mapping->a_ops = &balloon_aops;
#endif
@@ -913,13 +912,13 @@ static int virtballoon_probe(struct virt
*/
if (virtqueue_get_vring_size(vb->free_page_vq) < 2) {
err = -ENOSPC;
- goto out_del_vqs;
+ goto out_iput;
}
vb->balloon_wq = alloc_workqueue("balloon-wq",
WQ_FREEZABLE | WQ_CPU_INTENSIVE, 0);
if (!vb->balloon_wq) {
err = -ENOMEM;
- goto out_del_vqs;
+ goto out_iput;
}
INIT_WORK(&vb->report_free_page_work, report_free_page_func);
vb->cmd_id_received_cache = VIRTIO_BALLOON_CMD_ID_STOP;
@@ -953,6 +952,12 @@ static int virtballoon_probe(struct virt
out_del_balloon_wq:
if (virtio_has_feature(vdev, VIRTIO_BALLOON_F_FREE_PAGE_HINT))
destroy_workqueue(vb->balloon_wq);
+out_iput:
+#ifdef CONFIG_BALLOON_COMPACTION
+ iput(vb->vb_dev_info.inode);
+out_kern_unmount:
+ kern_unmount(balloon_mnt);
+#endif
out_del_vqs:
vdev->config->del_vqs(vdev);