[IMPALA-3378] HiveUdfCall::Open() produces unsynchronized access to JniUtil::global_refs_ vector

• Type: Bug
• Status: Resolved
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: Impala 2.5.0
• Fix Version/s: Impala 2.6.0, impala 2.5.1
• Component/s: Backend
• Labels: crash
• Target Version: Impala 2.6.0, impala 2.5.1
• Assignee: Skye Wanderman-Milne
• Reporter: Skye Wanderman-Milne
• Created: 19/Apr/16 21:28
• Updated: 04/May/16 09:51
• Resolved: 26/Apr/16 18:16

Description

HiveUdfCall::Open() calls JniUtil::GetGlobalClassRef(), which in turn calls JniUtil::LocalToGlobalRef(), which appends to the static std::vector global_refs_. This path can be running multiple times simultaneously due to multiple Java UDF calls across multiple fragments in a single query or multiple queries, resulting in unsynchronized access to global_refs_.

In other places, GetGlobalClassRef() and LocalToGlobalRef() are used during process initialization in the main thread, which is probably the intended use case.

Issue Links

• relates to: IMPALA-3379 HBaseTableWriter::CreatePutList() produces unsynchronized access to JniUtil::global_refs_ vector