[SLING-5525] Potential NPE / race condition with unregistered resource providers

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: Resource Resolver 1.4.0, Resource Resolver 1.4.2
• Fix Version/s: Resource Resolver 1.4.4
• Component/s: ResourceResolver
• Assignee: Carsten Ziegeler
• Reporter: Carsten Ziegeler
• Created: 17/Feb/16 08:41
• Updated: 26/Feb/16 12:19
• Resolved: 17/Feb/16 08:50

Description

There is a race condition with unregistering provider handlers and iterating over them. For example this NPE might happen in such a case:

15.02.2016 09:17:02.485 WARN [sling-oak-observation-68] org.apache.jackrabbit.oak.jcr.observation.ChangeProcessor Error while dispatching observation events for /*[1b, oak:Unstructured, sling:Folder, no local]
java.lang.NullPointerException: null
at org.apache.sling.resourceresolver.impl.providers.stateful.ProviderManager.authenticate(ProviderManager.java:156)
at org.apache.sling.resourceresolver.impl.providers.stateful.ProviderManager.getOrCreateProvider(ProviderManager.java:85)
at org.apache.sling.resourceresolver.impl.providers.stateful.ProviderManager$1$1.seek(ProviderManager.java:213)
at org.apache.sling.resourceresolver.impl.providers.stateful.ProviderManager$1$1.seek(ProviderManager.java:205)
at org.apache.sling.resourceresolver.impl.helper.AbstractIterator.hasNext(AbstractIterator.java:33)
at org.apache.sling.resourceresolver.impl.helper.ResourceResolverControl.adaptTo(ResourceResolverControl.java:474)
at org.apache.sling.resourceresolver.impl.ResourceResolverImpl.adaptTo(ResourceResolverImpl.java:830)