8304837: Classfile API throws IOOBE for MethodParameters attribute without parameter names

[SirYwell]

After merging master into #9862, we encountered test failures (e.g., https://github.com/SirYwell/jdk/actions/runs/4500940829/jobs/7923018438#step:9:2541). The Classfile API tries to read from constant pool index 0 if a MethodParameters attribute has an entry without name.

The fix is simply using readUtf8EntryOrNull instead of readUtf8Entry. The related code already correctly handles nullability.

I didn't find an appropriate test class so I added a new one. Let me know if there's a better place or if the test can be improved somehow.

As I don't have a JBS account, someone needs to create a bug report there for me. Thanks.

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Issue

• JDK-8304837: Classfile API throws IOOBE for MethodParameters attribute without parameter names

Reviewers

• Adam Sotona (@asotona - Committer)
• Julian Waters (@TheShermanTanker - Committer)
• Vicente Romero (@vicente-romero-oracle - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back SirYwell! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

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[liach]

Nice catch, issue opened at https://bugs.openjdk.org/browse/JDK-8304837 and marked as blocking compiler changes.

[mlbridge]

Webrevs

• 02: Full - Incremental (b77cc1b5)
• 01: Full - Incremental (f4b8062c)
• 00: Full (4a94bb17)

[TheShermanTanker]

Oops, looks like I was too late to create the issue haha

[SirYwell]

Thanks for the review. I moved the comment and changed to @bug.

[asotona]

It looks good, thank you for finding and fixing the bug.

[TheShermanTanker]

Great work, feel free to @ me if you need a quick sponsor once you integrate it

[jddarcy]

And just to double-check, the JVMS does allow the parameter name information to be missing even if the access flags are defined:
https://docs.oracle.com/javase/specs/jvms/se20/html/jvms-4.html#jvms-4.7.24

name_index

The value of the name_index item must either be zero or a valid index into the constant_pool table.

If the value of the name_index item is zero, then this parameters element indicates a formal parameter with no name.

If the value of the name_index item is nonzero, the constant_pool entry at that index must be a CONSTANT_Utf8_info structure representing a valid unqualified name denoting a formal parameter ([§4.2.2](https://docs.oracle.com/javase/specs/jvms/se20/html/jvms-4.html#jvms-4.2.2)).

[bridgekeeper]

@SirYwell This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply add a new comment to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[TheShermanTanker]

Keeping alive

[vicente-romero-oracle]

looks good

[openjdk]

⚠️ @SirYwell the full name on your profile does not match the author name in this pull requests' HEAD commit. If this pull request gets integrated then the author name from this pull requests' HEAD commit will be used for the resulting commit. If you wish to push a new commit with a different author name, then please run the following commands in a local repository of your personal fork:

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[openjdk]

@SirYwell This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8304837: Classfile API throws IOOBE for MethodParameters attribute without parameter names

Reviewed-by: asotona, jwaters, vromero

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 489 new commits pushed to the master branch:

• d43a5a2: 8307135: java/awt/dnd/NotReallySerializableTest/NotReallySerializableTest.java failed
• 1f68924: 8306955: Open source several JComboBox jtreg tests
• b8de394: 8307080: Open source some more JComboBox jtreg tests
• 4818c79: 8307110: zero build broken after JDK-8304265
• da9efee: 8296935: Arrays.asList() can return a List that throws undocumented ArrayStoreException
• 05af487: 8306681: Open source more AWT DnD related tests
• ec5c792: 8306133: Open source few AWT Drag & Drop related tests
• 6d6f726: 8307078: Opensource and clean up five more AWT Focus related tests
• 89711f3: 8307079: Update test java/awt/Choice/DragOffNoSelect.java
• 9ff5550: 8307077: Convert CRLF to LF in java.xml.crypto
• ... and 479 more: https://git.openjdk.org/jdk/compare/6fa25cc134e8a6787490e080fb98c2d61cf0b049...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@asotona, @TheShermanTanker, @vicente-romero-oracle) but any other Committer may sponsor as well.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[SirYwell]

/integrate

[SirYwell]

Thank you for your review, @vicente-romero-oracle.

[openjdk]

@SirYwell
Your change (at version b77cc1b) is now ready to be sponsored by a Committer.

[TheShermanTanker]

Nice! :)

[TheShermanTanker]

/sponsor

[openjdk]

Going to push as commit a2d3fc8.
Since your change was applied there have been 489 commits pushed to the master branch:

• d43a5a2: 8307135: java/awt/dnd/NotReallySerializableTest/NotReallySerializableTest.java failed
• 1f68924: 8306955: Open source several JComboBox jtreg tests
• b8de394: 8307080: Open source some more JComboBox jtreg tests
• 4818c79: 8307110: zero build broken after JDK-8304265
• da9efee: 8296935: Arrays.asList() can return a List that throws undocumented ArrayStoreException
• 05af487: 8306681: Open source more AWT DnD related tests
• ec5c792: 8306133: Open source few AWT Drag & Drop related tests
• 6d6f726: 8307078: Opensource and clean up five more AWT Focus related tests
• 89711f3: 8307079: Update test java/awt/Choice/DragOffNoSelect.java
• 9ff5550: 8307077: Convert CRLF to LF in java.xml.crypto
• ... and 479 more: https://git.openjdk.org/jdk/compare/6fa25cc134e8a6787490e080fb98c2d61cf0b049...master

Your commit was automatically rebased without conflicts.

[openjdk]

@TheShermanTanker @SirYwell Pushed as commit a2d3fc8.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.