qemu: avoid memory leak while remove disk

Memset vhost_dev to zero in the vhost_dev_cleanup function.
This causes dev.vqs to be NULL, so that
vqs does not free up space when calling the g_free function.
This will result in a memory leak. But you can't release vqs
directly in the vhost_dev_cleanup function, because vhost_net
will also call this function, and vhost_net's vqs is assigned by array.
In order to solve this problem, we first save the pointer of vqs,
and release the space of vqs after vhost_dev_cleanup is called.

Signed-off-by: Jian Wang <wangjian161@huawei.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
index 7f21b4f9d6..61e2e57da9 100644
--- a/hw/scsi/vhost-scsi.c
+++ b/hw/scsi/vhost-scsi.c
@@ -215,6 +215,7 @@ static void vhost_scsi_unrealize(DeviceState *dev, Error **errp)
 {
     VirtIODevice *vdev = VIRTIO_DEVICE(dev);
     VHostSCSICommon *vsc = VHOST_SCSI_COMMON(dev);
+    struct vhost_virtqueue *vqs = vsc->dev.vqs;
 
     migrate_del_blocker(vsc->migration_blocker);
     error_free(vsc->migration_blocker);
@@ -223,7 +224,7 @@ static void vhost_scsi_unrealize(DeviceState *dev, Error **errp)
     vhost_scsi_set_status(vdev, 0);
 
     vhost_dev_cleanup(&vsc->dev);
-    g_free(vsc->dev.vqs);
+    g_free(vqs);
 
     virtio_scsi_common_unrealize(dev, errp);
 }