diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 8a8083207be4c..4bdcd2b326bd4 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -1119,6 +1119,12 @@ bool mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
 		mptcp_data_lock(subflow->conn);
 		if (sk_stream_memory_free(sk))
 			__mptcp_check_push(subflow->conn, sk);
+
+		/* on fallback we just need to ignore the msk-level snd_una, as
+		 * this is really plain TCP
+		 */
+		msk->snd_una = READ_ONCE(msk->snd_nxt);
+
 		__mptcp_data_acked(subflow->conn);
 		mptcp_data_unlock(subflow->conn);
 		return true;
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
index 086303eccdbf6..e1d14e3766e28 100644
--- a/net/mptcp/protocol.c
+++ b/net/mptcp/protocol.c
@@ -958,12 +958,6 @@ static void __mptcp_clean_una(struct sock *sk)
 	struct mptcp_data_frag *dtmp, *dfrag;
 	u64 snd_una;
 
-	/* on fallback we just need to ignore snd_una, as this is really
-	 * plain TCP
-	 */
-	if (__mptcp_check_fallback(msk))
-		msk->snd_una = READ_ONCE(msk->snd_nxt);
-
 	snd_una = msk->snd_una;
 	list_for_each_entry_safe(dfrag, dtmp, &msk->rtx_queue, list) {
 		if (after64(dfrag->data_seq + dfrag->data_len, snd_una))