From 093bdd1a59bf4d98fda580701314068dbdc27226 Mon Sep 17 00:00:00 2001
From: Martijn van Groningen <martijn.v.groningen@gmail.com>
Date: Fri, 21 Feb 2025 11:48:21 +0100
Subject: [PATCH] Hold store reference in
 InternalEngine#performActionWithDirectoryReader(...) (#123010)

This method gets called from `InternalEngine#resolveDocVersion(...)`, which gets during indexing (via `InternalEngine.index(...)`).

When `InternalEngine.index(...)` gets invoked, the InternalEngine only ensures that it holds a ref to the engine via Engine#acquireEnsureOpenRef(), but this doesn't ensure whether it holds a reference to the store.

Closes #122974

* Update docs/changelog/123010.yaml
---
 docs/changelog/123010.yaml                                  | 6 ++++++
 .../java/org/elasticsearch/index/engine/InternalEngine.java | 6 +++++-
 2 files changed, 11 insertions(+), 1 deletion(-)
 create mode 100644 docs/changelog/123010.yaml

diff --git a/docs/changelog/123010.yaml b/docs/changelog/123010.yaml
new file mode 100644
index 0000000000000..3d95d775b8a54
--- /dev/null
+++ b/docs/changelog/123010.yaml
@@ -0,0 +1,6 @@
+pr: 123010
+summary: Hold store reference in `InternalEngine#performActionWithDirectoryReader(...)`
+area: Engine
+type: bug
+issues:
+ - 122974
diff --git a/server/src/main/java/org/elasticsearch/index/engine/InternalEngine.java b/server/src/main/java/org/elasticsearch/index/engine/InternalEngine.java
index a2cc10d417b72..a106893a32b04 100644
--- a/server/src/main/java/org/elasticsearch/index/engine/InternalEngine.java
+++ b/server/src/main/java/org/elasticsearch/index/engine/InternalEngine.java
@@ -3452,7 +3452,9 @@ protected long getPreCommitSegmentGeneration() {
     <T> T performActionWithDirectoryReader(SearcherScope scope, CheckedFunction<DirectoryReader, T, IOException> action)
         throws EngineException {
         assert scope == SearcherScope.INTERNAL : "performActionWithDirectoryReader(...) isn't prepared for external usage";
-        assert store.hasReferences();
+        if (store.tryIncRef() == false) {
+            throw new AlreadyClosedException(shardId + " store is closed", failedEngine.get());
+        }
         try {
             ReferenceManager<ElasticsearchDirectoryReader> referenceManager = getReferenceManager(scope);
             ElasticsearchDirectoryReader acquire = referenceManager.acquire();
@@ -3468,6 +3470,8 @@ <T> T performActionWithDirectoryReader(SearcherScope scope, CheckedFunction<Dire
             ensureOpen(ex); // throw EngineCloseException here if we are already closed
             logger.error("failed to perform action with directory reader", ex);
             throw new EngineException(shardId, "failed to perform action with directory reader", ex);
+        } finally {
+            store.decRef();
         }
     }
 }