[BUG] Null pointer exception in geopoint sort with security

[ajleong623]

What is the bug?
When users run a search with sorting and their cluster has security configurations, the method getPointValues is called from the directory reader. However, when security is configured, DlsFlsFilterLeafReader calls getPointValues. There are cases where the field that is being checked is null, reproducible by the issue linked here opensearch-project/OpenSearch#18420.

How can one reproduce the bug?
Follow the steps here: opensearch-project/OpenSearch#18420 (comment).

What is the expected behavior?
I would expect for the case of a null field to be handled.

What is your host/environment?

• OS: [e.g. iOS]
• Version [e.g. 22]
• Plugins

Do you have any screenshots?
If applicable, add screenshots to help explain your problem.

Do you have any additional context?
Add any other context about the problem.

[cwperks]

I think its related to #5303

Edit: Not related

The change where stripKeywordSuffix was introduced is 3c635c9

In 2.19 and below, handleKeyword had a null check.

[cwperks]

[Triage] Thank you for filing this issue @ajleong623 ! Will the fix for this be in core or in the security repo? I saw the PR in core, but with the test could not follow how it fixed this particular issue and what change caused the regression in behavior.

[ajleong623]

@cwperks The fix will actually be in the core repo. After some discussion, @nibix pointed out that there are calls to the leaf reader where the field is null #5504 (comment). This happens when the sort is being processed and the getPointValues() function could pass the field in as null. I stepped through the test to confirm this. Therefore, in the core repository, that is where I added the null check.

[ajleong623]

@nibix @cwperks Should I close this issue and the pr on the security end?

[cwperks]

@ajleong623 I think this PR is the right way to go.

I see the same error in opensearch-project/OpenSearch-Dashboards#9873