diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index f8e8dc28693e03baddf1bf275a64c191871d8bcf..af663939b2d97c57fcd35b93cfd55b5759cb681b 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2509,6 +2509,7 @@ static void tcp_rtx_queue_purge(struct sock *sk)
 {
 	struct rb_node *p = rb_first(&sk->tcp_rtx_queue);
 
+	tcp_sk(sk)->highest_sack = NULL;
 	while (p) {
 		struct sk_buff *skb = rb_to_skb(p);
 
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 658348cd48fb625a53cb5928be685f42e4e6ea79..b259ed4d71cef778f8927f23669151b87293c492 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -3145,6 +3145,7 @@ static int tcp_clean_rtx_queue(struct sock *sk, u32 prior_fack,
 			tp->retransmit_skb_hint = NULL;
 		if (unlikely(skb == tp->lost_skb_hint))
 			tp->lost_skb_hint = NULL;
+		tcp_highest_sack_replace(sk, skb, next);
 		tcp_rtx_queue_unlink_and_free(skb, sk);
 	}
 
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c
index e3ce1f56f845678e12717aa1668f79b0331ef982..8cc98a367241ffa4957e2e0fafcb723d334c68fa 100644
--- a/net/ipv4/tcp_output.c
+++ b/net/ipv4/tcp_output.c
@@ -3157,6 +3157,7 @@ int tcp_send_synack(struct sock *sk)
 			if (!nskb)
 				return -ENOMEM;
 			INIT_LIST_HEAD(&nskb->tcp_tsorted_anchor);
+			tcp_highest_sack_replace(sk, skb, nskb);
 			tcp_rtx_queue_unlink_and_free(skb, sk);
 			__skb_header_release(nskb);
 			tcp_rbtree_insert(&sk->tcp_rtx_queue, nskb);