diff --git a/include/net/tcp.h b/include/net/tcp.h
index a385797f160a..c6ecd455edab 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -736,9 +736,7 @@ static inline __u32 tcp_current_ssthresh(const struct sock *sk)
 
 static inline void tcp_sync_left_out(struct tcp_sock *tp)
 {
-	if (tp->rx_opt.sack_ok &&
-	    (tp->sacked_out >= tp->packets_out - tp->lost_out))
-		tp->sacked_out = tp->packets_out - tp->lost_out;
+	BUG_ON(tp->sacked_out + tp->lost_out > tp->packets_out);
 	tp->left_out = tp->sacked_out + tp->lost_out;
 }