struct sk_buff *skb = tcp_write_queue_tail(sk);
 	u32 tsflags = sockc->tsflags;
 
+	if (unlikely(!skb))
+		skb = skb_rb_last(&sk->tcp_rtx_queue);
+
 	if (tsflags && skb) {
 		struct skb_shared_info *shinfo = skb_shinfo(skb);
 		struct tcp_skb_cb *tcb = TCP_SKB_CB(skb);
-- 
2.51.0[PATCH 6.19 371/781] tcp: tcp_tx_timestamp() must look at the rtx queueGreg Kroah-Hartman <gregkh@linuxfoundation.org> undefinedstable@vger.kernel.org undefined undefined undefined undefined undefined undefined™