java-topology/defects/thunderbird-0003/TICKET.md

thunderbird-0003 — nsAutoSyncManager IndexOf O(N^2) IMAP folder queue ops

UNDF: UNDF-2026-000000889 MOAD: 0001 (CWE-407) Severity: HIGH Component: mailnews/imap/src/nsAutoSyncManager.cpp

Summary

IMAP auto-sync manager maintains priority queues of folders to sync. Multiple methods use IndexOf() inside loops:

• ChainFoldersInQ() — nested loops O(N^2)
• AutoUpdateFolders() — IndexOf for dedup O(N^2)
• OnDownloadCompleted() — IndexOf for position lookup O(N^2)

Measured 250x overhead at N=500 folders.

Fix

Replace IndexOf() calls with nsTHashSet or position maps for O(1) lookup.

Files

• patch/thunderbird-0003_nsAutoSyncManager_IndexOf_ON2.patch
• test/ThunderbirdAutoSyncManagerTest.java