diff --git a/include/haproxy/mux_quic.h b/include/haproxy/mux_quic.h
index f0c0a430e..715f7e9f5 100644
--- a/include/haproxy/mux_quic.h
+++ b/include/haproxy/mux_quic.h
@@ -11,6 +11,7 @@
 #include <haproxy/api.h>
 #include <haproxy/connection.h>
 #include <haproxy/mux_quic-t.h>
+#include <haproxy/stream.h>
 #include <haproxy/xprt_quic-t.h>
 
 struct qcs *qcs_new(struct qcc *qcc, uint64_t id, enum qcs_type type);
@@ -104,6 +105,19 @@ static inline struct qc_stream_desc *qcc_get_stream(struct qcc *qcc, uint64_t id
 	return eb64_entry(node, struct qc_stream_desc, by_id);
 }
 
+static inline struct conn_stream *qc_attach_cs(struct qcs *qcs, struct buffer *buf)
+{
+	struct conn_stream *cs = cs_new();
+	if (!cs)
+		return NULL;
+	cs_attach_endp(cs, &qcs->qcc->conn->obj_type, qcs);
+
+	cs->ctx = qcs;
+	stream_new(qcs->qcc->conn->owner, cs, buf);
+
+	return cs;
+}
+
 #endif /* USE_QUIC */
 
 #endif /* _HAPROXY_MUX_QUIC_H */
diff --git a/src/h3.c b/src/h3.c
index a7968454a..3cce59563 100644
--- a/src/h3.c
+++ b/src/h3.c
@@ -24,12 +24,11 @@
 #include <haproxy/http.h>
 #include <haproxy/htx.h>
 #include <haproxy/istbuf.h>
-#include <haproxy/mux_quic-t.h>
+#include <haproxy/mux_quic.h>
 #include <haproxy/pool.h>
 #include <haproxy/qpack-dec.h>
 #include <haproxy/qpack-enc.h>
 #include <haproxy/quic_enc.h>
-#include <haproxy/stream.h>
 #include <haproxy/tools.h>
 #include <haproxy/xprt_quic.h>
 
@@ -174,14 +173,10 @@ static int h3_headers_to_htx(struct qcs *qcs, struct buffer *buf, uint64_t len,
 	if (fin)
 		htx->flags |= HTX_FL_EOM;
 
-	cs = cs_new();
+	cs = qc_attach_cs(qcs, &htx_buf);
 	if (!cs)
 		return 1;
-	cs_attach_endp(cs, &qcs->qcc->conn->obj_type, qcs);
-
 	cs->flags |= CS_FL_NOT_FIRST;
-	cs->ctx = qcs;
-	stream_new(qcs->qcc->conn->owner, cs, &htx_buf);
 
 	/* buffer is transferred to conn_stream and set to NULL
 	 * except on stream creation error.
diff --git a/src/hq_interop.c b/src/hq_interop.c
index 0e5561d8a..79283736c 100644
--- a/src/hq_interop.c
+++ b/src/hq_interop.c
@@ -6,8 +6,7 @@
 #include <haproxy/dynbuf.h>
 #include <haproxy/htx.h>
 #include <haproxy/http.h>
-#include <haproxy/mux_quic-t.h>
-#include <haproxy/stream.h>
+#include <haproxy/mux_quic.h>
 
 static int hq_interop_decode_qcs(struct qcs *qcs, int fin, void *ctx)
 {
@@ -72,12 +71,9 @@ static int hq_interop_decode_qcs(struct qcs *qcs, int fin, void *ctx)
 	htx_add_endof(htx, HTX_BLK_EOH);
 	htx_to_buf(htx, &htx_buf);
 
-	cs = cs_new();
+	cs = qc_attach_cs(qcs, &htx_buf);
 	if (!cs)
 		return -1;
-	cs_attach_endp(cs, &qcs->qcc->conn->obj_type, qcs);
-	cs->ctx = qcs;
-	stream_new(qcs->qcc->conn->owner, cs, &htx_buf);
 
 	b_del(rxbuf, b_data(rxbuf));
 	b_free(&htx_buf);