From 5181a2a9b115a5da65b2b6858cdc3db17bbea732 Mon Sep 17 00:00:00 2001
From: Michael Vines <mvines@gmail.com>
Date: Wed, 6 Feb 2019 12:46:33 -0800
Subject: [PATCH] Guard against invalid tick heights

---
 src/last_id_queue.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/last_id_queue.rs b/src/last_id_queue.rs
index 80acaee4aa..4242fc4356 100644
--- a/src/last_id_queue.rs
+++ b/src/last_id_queue.rs
@@ -103,7 +103,9 @@ impl LastIdQueue {
         let current_tick_height = self.tick_height;
         let mut total = 0;
         for (tick_height, stake) in ticks_and_stakes.iter() {
-            if ((current_tick_height - tick_height) as usize) < MAX_ENTRY_IDS {
+            if current_tick_height >= *tick_height
+                && ((current_tick_height - tick_height) as usize) < MAX_ENTRY_IDS
+            {
                 total += stake;
                 if total > supermajority_stake {
                     return self.tick_height_to_timestamp(*tick_height);