diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index cb44b6c6ba..cac0b6c7ba 100644
--- a/block/qcow2-cluster.c
+++ b/block/qcow2-cluster.c
@@ -474,9 +474,10 @@ static bool coroutine_fn do_perform_cow_encrypt(BlockDriverState *bs,
         assert(QEMU_IS_ALIGNED(offset_in_cluster, BDRV_SECTOR_SIZE));
         assert(QEMU_IS_ALIGNED(bytes, BDRV_SECTOR_SIZE));
         assert(s->crypto);
-        if (qcow2_co_encrypt(bs, cluster_offset,
-                             src_cluster_offset + offset_in_cluster,
-                             buffer, bytes) < 0) {
+        if (qcow2_co_encrypt(bs,
+                start_of_cluster(s, cluster_offset + offset_in_cluster),
+                src_cluster_offset + offset_in_cluster,
+                buffer, bytes) < 0) {
             return false;
         }
     }