8277444: Data race between JvmtiClassFileReconstituter::copy_bytecodes and class linking

[chadrako]

A clean backport of https://bugs.openjdk.org/browse/JDK-8277444

This fixes a race condition that occurs when a class is simultaneously retransformed via the Instrumentation API and linked. This can lead to invalid bytecode which will cause a VerifyError. Even worse, if class verifying is turned off, which it is by default for java.* classes, this will cause the JVM to crash/segfault.

The included test test/jdk/java/lang/instrument/RetransformBigClassTest.java fails before the patch and passes after

---

Progress

• JDK-8277444 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8277444: Data race between JvmtiClassFileReconstituter::copy_bytecodes and class linking (Bug - P4 - Approved)

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk25u.git pull/197/head:pull/197
$ git checkout pull/197

Update a local copy of the PR:
$ git checkout pull/197
$ git pull https://git.openjdk.org/jdk25u.git pull/197/head

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$ git pr checkout 197

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[bridgekeeper]

👋 Welcome back chadrako! 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]

@chadrako 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:

8277444: Data race between JvmtiClassFileReconstituter::copy_bytecodes and class linking

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At the time when this comment was updated there had been 15 new commits pushed to the master branch:

• 43d9fcc: 8366147: ZGC: ZPageAllocator::cleanup_failed_commit_single_partition may leak memory
• f542b8f: 8363966: GHA: Switch cross-compiling sysroots to Debian trixie
• f80b3a0: 8346952: GetGraphicsStressTest.java fails: Native resources unavailable
• ... and 12 more: https://git.openjdk.org/jdk25u/compare/b105b7b5d6dd85ab3f1f8e6185848239dbf18521...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.

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[openjdk]

This backport pull request has now been updated with issue from the original commit.

[openjdk]

⚠️ @chadrako This change is now ready for you to apply for maintainer approval. This can be done directly in each associated issue or by using the /approval command.

[mlbridge]

Webrevs

• 00: Full (4a2fa450)

[chadrako]

/approval request A clean backport that fixes a race condition that occurs when a class is simultaneously retransformed via the Instrumentation API and linked. This can lead to invalid bytecode which will cause a VerifyError. Even worse, if class verifying is turned off, which it is by default for java.* classes, this will cause the JVM to crash/segfault. The included test test/jdk/java/lang/instrument/RetransformBigClassTest.java fails before the patch and passes after

[openjdk]

@chadrako
8277444: The approval request has been created successfully.

[chadrako]

I ran the failing GHA test locally and it passes consistently
test/jdk/java/lang/Thread/virtual/stress/GetStackTraceALotWhenBlocking.java

[chadrako]

Test passed on GHA rerun

[chadrako]

/integrate

[openjdk]

@chadrako
Your change (at version 4a2fa45) is now ready to be sponsored by a Committer.

[phohensee]

/sponsor

[openjdk]

Going to push as commit 8149318.
Since your change was applied there have been 31 commits pushed to the master branch:

• 4bc1dc3: 8023263: [TESTBUG] Test closed/java/awt/Focus/InactiveWindowTest/InactiveFocusRace fails due to not enough time to initialize graphic components
• c357a2f: 8364184: [REDO] AArch64: [VectorAPI] sve vector math operations are not supported after JDK-8353217
• d930cc5: 8162380: [TEST_BUG] MouseEvent/.../AltGraphModifierTest.java has only "Fail" button
• ... and 28 more: https://git.openjdk.org/jdk25u/compare/b105b7b5d6dd85ab3f1f8e6185848239dbf18521...master

Your commit was automatically rebased without conflicts.

[openjdk]

@phohensee @chadrako Pushed as commit 8149318.

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