diff --git a/src/stream_interface.c b/src/stream_interface.c
index 4b5b760c8..52aa7c43d 100644
--- a/src/stream_interface.c
+++ b/src/stream_interface.c
@@ -760,8 +760,12 @@ static struct task * si_cs_send(struct conn_stream *cs)
 struct task *si_cs_io_cb(struct task *t, void *ctx, unsigned short state)
 {
 	struct stream_interface *si = ctx;
+	struct conn_stream *cs = objt_cs(si->end);
+
+	if (!cs)
+		return NULL;
 	if (!(si->wait_list.wait_reason & SUB_CAN_SEND))
-		si_cs_send(__objt_cs(si->end));
+		si_cs_send(cs);
 	return (NULL);
 }