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-rw-r--r--docs/interop/vhost-user.rst4
-rw-r--r--hw/virtio/vhost-user.c21
2 files changed, 22 insertions, 3 deletions
diff --git a/docs/interop/vhost-user.rst b/docs/interop/vhost-user.rst
index d1ed39dfa0..d8419fd2f1 100644
--- a/docs/interop/vhost-user.rst
+++ b/docs/interop/vhost-user.rst
@@ -1839,7 +1839,9 @@ is sent by the front-end.
   When the ``VHOST_USER_PROTOCOL_F_SHARED_OBJECT`` protocol
   feature has been successfully negotiated, this message can be submitted
   by the backend to remove themselves from to the virtio-dmabuf shared
-  table API. The shared table will remove the back-end device associated with
+  table API. Only the back-end owning the entry (i.e., the one that first added
+  it) will have permission to remove it. Otherwise, the message is ignored.
+  The shared table will remove the back-end device associated with
   the UUID. If ``VHOST_USER_PROTOCOL_F_REPLY_ACK`` is negotiated, and the
   back-end sets the ``VHOST_USER_NEED_REPLY`` flag, the front-end must respond
   with zero when operation is successfully completed, or non-zero otherwise.
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index a1eea8547e..9d654efd3d 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1611,11 +1611,27 @@ vhost_user_backend_handle_shared_object_add(struct vhost_dev *dev,
 }
 
 static int
-vhost_user_backend_handle_shared_object_remove(VhostUserShared *object)
+vhost_user_backend_handle_shared_object_remove(struct vhost_dev *dev,
+                                               VhostUserShared *object)
 {
     QemuUUID uuid;
 
     memcpy(uuid.data, object->uuid, sizeof(object->uuid));
+    switch (virtio_object_type(&uuid)) {
+    case TYPE_VHOST_DEV:
+    {
+        struct vhost_dev *owner = virtio_lookup_vhost_device(&uuid);
+        if (dev != owner) {
+            /* Not allowed to remove non-owned entries */
+            return 0;
+        }
+        break;
+    }
+    default:
+        /* Not allowed to remove non-owned entries */
+        return 0;
+    }
+
     return virtio_remove_resource(&uuid);
 }
 
@@ -1794,7 +1810,8 @@ static gboolean backend_read(QIOChannel *ioc, GIOCondition condition,
         ret = vhost_user_backend_handle_shared_object_add(dev, &payload.object);
         break;
     case VHOST_USER_BACKEND_SHARED_OBJECT_REMOVE:
-        ret = vhost_user_backend_handle_shared_object_remove(&payload.object);
+        ret = vhost_user_backend_handle_shared_object_remove(dev,
+                                                             &payload.object);
         break;
     case VHOST_USER_BACKEND_SHARED_OBJECT_LOOKUP:
         ret = vhost_user_backend_handle_shared_object_lookup(dev->opaque, ioc,