Fix typo
diff --git a/test/core/util/passthru_endpoint.c b/test/core/util/passthru_endpoint.c
index 1591558..ae955b1 100644
--- a/test/core/util/passthru_endpoint.c
+++ b/test/core/util/passthru_endpoint.c
@@ -84,7 +84,7 @@
ok = false;
} else if (m->on_read != NULL) {
for (size_t i = 0; i < slices->count; i++) {
- gpr_slice_buffer_add(&m->read_buffer, gpr_slice_ref(slices->slices[i]));
+ gpr_slice_buffer_add(m->on_read_out, gpr_slice_ref(slices->slices[i]));
}
grpc_exec_ctx_enqueue(exec_ctx, m->on_read, true, NULL);
m->on_read = NULL;