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

[chadrako]

Backport of https://bugs.openjdk.org/browse/JDK-8277444. The backport was not clean but the fixes were trivial naming differences

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

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Progress

• Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• 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 - Requested)

Reviewers

• Andrew John Hughes (@gnu-andrew - Reviewer)

Reviewing

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[chadrako]

Waiting to request maintainer approval until backport is merged in newer JDKs

[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]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

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

[mlbridge]

Webrevs

• 00: Full (e5c5bf15)

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@chadrako 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 issue a /touch or /keepalive command to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[chadrako]

/keepalive

[openjdk]

@chadrako The pull request is being re-evaluated and the inactivity timeout has been reset.

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[chadrako]

/open

[openjdk]

@chadrako This pull request is now open

[chadrako]

/approval request An almost clean backport (trivial naming differences) 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. This patch has been in jdk25 and Corretto 11 for 6 months.

[openjdk]

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

[chadrako]

/approval request Re-requesting now that this has been backported to jdk17. An almost clean backport (trivial naming differences) 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. This patch has been in jdk25 and Corretto 11 for 6 months.

[openjdk]

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

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@chadrako 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 issue a /touch or /keepalive command to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[chadrako]

/touch

[openjdk]

@chadrako The pull request is being re-evaluated and the inactivity timeout has been reset.

[chadrako]

/template

[openjdk]

@chadrako Missing command 'append', usage: /template append

[chadrako]

/template append

[openjdk]

@chadrako The pull request template has been appended to the pull request body

[gnu-andrew]

This looks good to me. 11u lacks JDK-8233913 which added the earlier Thread::current() in getBytecodes so we don't have the second hunk in jvmtiEnv.cpp and have to call Thread::current() in the third. But otherwise the change is the same.

Test shows the patch works too.

[bridgekeeper]

@chadrako 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 issue a /touch or /keepalive command to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!