From 7d3aa91bf4c3b68442b92d6da7a4692ef1e64e6a Mon Sep 17 00:00:00 2001
From: Philippe Antoine <pantoine@oisf.net>
Date: Tue, 30 May 2023 12:08:25 +0200
Subject: [PATCH] mqtt: fix quadratic complexity

get_tx_by_pkt_id loops only over the last transactions
in case there is a transaction flood

Ticket: #6100
---
 rust/src/mqtt/mqtt.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/rust/src/mqtt/mqtt.rs b/rust/src/mqtt/mqtt.rs
index 6149ce5982..f1c37d83c8 100644
--- a/rust/src/mqtt/mqtt.rs
+++ b/rust/src/mqtt/mqtt.rs
@@ -170,7 +170,7 @@ impl MQTTState {
     }
 
     pub fn get_tx_by_pkt_id(&mut self, pkt_id: u32) -> Option<&mut MQTTTransaction> {
-        for tx in &mut self.transactions {
+        for tx in &mut self.transactions.range_mut(self.tx_index_completed..) {
             if !tx.complete {
                 if let Some(mpktid) = tx.pkt_id {
                     if mpktid == pkt_id {