--- zzzz-none-000/linux-3.18.24/net/ipv4/tcp_input.c	2015-10-31 20:39:51.000000000 +0000
+++ rtl96-5690pro-762/linux-3.18.24/net/ipv4/tcp_input.c	2024-08-14 08:36:37.000000000 +0000
@@ -2515,6 +2515,9 @@
 	int newly_acked_sacked = prior_unsacked -
 				 (tp->packets_out - tp->sacked_out);
 
+	if (newly_acked_sacked <= 0 || WARN_ON_ONCE(!tp->prior_cwnd))
+		return;
+
 	tp->prr_delivered += newly_acked_sacked;
 	if (tcp_packets_in_flight(tp) > tp->snd_ssthresh) {
 		u64 dividend = (u64)tp->snd_ssthresh * tp->prr_delivered +