8374343: Fix SIGSEGV when lib/modules is unreadable

[bulasevich]

This pull request contains a backport of commit 48846744 from the openjdk/jdk repository.

The simple change fixes SIGSEGV crash during startup if the runtime image (lib/modules) exists but is unreadable.

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Progress

• JDK-8374343 needs maintainer approval
• Change must not contain extraneous whitespace
• Commit message must refer to an issue

Issue

• JDK-8374343: Fix SIGSEGV when lib/modules is unreadable (Bug - P4 - Approved)

Reviewing

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[bridgekeeper]

👋 Welcome back bulasevich! 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]

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

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

8374343: Fix SIGSEGV when lib/modules is unreadable

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At the time when this comment was updated there had been 65 new commits pushed to the master branch:

• f368f54: 8354695: Open source several swing tests batch7
• d417f3b: 8360395: sun/security/tools/keytool/i18n.java user country is current user location instead of the language
• f3829e6: 8320677: Printer tests use invalid '@run main/manual=yesno
• ... and 62 more: https://git.openjdk.org/jdk21u-dev/compare/b318d5cabba4f832084e16b09bce42d38f36e124...master

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[openjdk]

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

[openjdk]

⚠️ @bulasevich 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 (4ef6daf0)

[GoeLin]

Hi @bulasevich
please first backport to 26 and 25.
I remove the labels in the meantime.

[bulasevich]

/approval request This simple change fixes a specific startup crash. The backport is clean and small, with low risk.

[openjdk]

@bulasevich
8374343: The approval request has been created successfully.