fix: prevent existing queue elements to be overwritten

Tenderize · Mar 28, 2024 · 8802715 · 8802715
1 parent 9659c19
commit 8802715
Showing 1 changed file with 5 additions and 0 deletions.
diff --git a/src/UnlockQueue.sol b/src/UnlockQueue.sol
@@ -19,6 +19,7 @@ pragma solidity >=0.8.19;
 
 library UnlockQueue {
     error QueueEmpty();
+    error IdExists();
 
     struct Item {
         uint256 id;
@@ -110,6 +111,10 @@ library UnlockQueue {
         uint256 tail = q._tail;
         uint256 newTail = unlock.id;
 
+        if (tail != 0) {
+            if (q.nodes[newTail].data.id != 0) revert IdExists();
+        }
+
         q.nodes[newTail].data = unlock;
         q.nodes[newTail].prev = tail;