[OAK-5649] Error in RefreshPolicy can lead to IndexNode lock leak

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.6.0
• Fix Version/s: 1.7.0, 1.6.1, 1.8.0
• Component/s: lucene
• Assignee: Chetan Mehrotra
• Reporter: Chetan Mehrotra
• Created: 14/Feb/17 08:19
• Updated: 06/Mar/17 13:51
• Resolved: 15/Feb/17 04:41

Description

IndexNode uses a ReadWriteLock which is "acquired" and "released".

 boolean acquire() {
        lock.readLock().lock();
        if (closed) {
            lock.readLock().unlock();
            return false;
        } else {
            refreshPolicy.refreshOnReadIfRequired(refreshCallback);
            return true;
        }
    }

Its possible that any exception thrown in RefreshPolicy#refreshOnReadIfRequired can lead to lock being acquired but not released causing the lock to be lost and any further attempt to close such IndexNode instance would block indefinitely.

As a fix the acquire call should account for any potential exception thrown in any call made from within that method call

Issue Links

• is related to: OAK-5661 Make NRT indexing resilient against unbounded growth