diff --git a/block/vhdx.c b/block/vhdx.c
index 68db9e0..c67772e 100644
--- a/block/vhdx.c
+++ b/block/vhdx.c
@@ -1165,7 +1165,7 @@
     /* per the spec, the address for a block is in units of 1MB */
     *new_offset = ROUND_UP(*new_offset, 1024 * 1024);
 
-    return bdrv_truncate(bs->file->bs, *new_offset + s->block_size);
+    return bdrv_truncate(bs->file, *new_offset + s->block_size);
 }
 
 /*