8273108: RunThese24H crashes with SEGV in markWord::displaced_mark_helper() after JDK-8268276

[asgibbons]

The base64 decoder overwrites memory past the end of its output buffer in certain cases. It will not overwrite if the encoded string length is < 64 bytes. It also will not overwrite if the encoded string length mod 64 is >= 16. So the case where it will overwrite is when the input string length (the encoded byte length) mod 64 is less than 16.

I also added a test case to detect this overrun.

---

Progress

• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed

Issues

• JDK-8273108: RunThese24H crashes with SEGV in markWord::displaced_mark_helper() after JDK-8268276
• JDK-8275427: RunThese24H.java failed with EXCEPTION_ACCESS_VIOLATION in java.util.ArrayList.add
• JDK-8272809: JFR thread sampler SI_KERNEL SEGV in metaspace::VirtualSpaceList::contains

Reviewing

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Checkout this PR locally:
$ git fetch https://git.openjdk.java.net/jdk pull/6786/head:pull/6786
$ git checkout pull/6786

Update a local copy of the PR:
$ git checkout pull/6786
$ git pull https://git.openjdk.java.net/jdk pull/6786/head

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$ git pr checkout 6786

View PR using the GUI difftool:
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https://git.openjdk.java.net/jdk/pull/6786.diff

[bridgekeeper]

👋 Welcome back asgibbons! 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.

[asgibbons]

/solves 8275427

[asgibbons]

/label hotspot

[openjdk]

@asgibbons
Adding additional issue to solves list: 8275427: RunThese24H.java failed with EXCEPTION_ACCESS_VIOLATION in java.util.ArrayList.add.

[openjdk]

@asgibbons
The hotspot label was successfully added.

[asgibbons]

/label hotspot-compiler

[openjdk]

@asgibbons
The hotspot-compiler label was successfully added.

[mlbridge]

Webrevs

• 00: Full (2df7ab2f)

[asgibbons]

/solves JDK-8275427

[openjdk]

@asgibbons
Updating description of additional solved issue: 8275427: RunThese24H.java failed with EXCEPTION_ACCESS_VIOLATION in java.util.ArrayList.add.

[asgibbons]

/solves 8272809

[openjdk]

@asgibbons
Adding additional issue to solves list: 8272809: JFR thread sampler SI_KERNEL SEGV in metaspace::VirtualSpaceList::contains.

[sviswa7]

@asgibbons The change looks good to me. Could you please create this PR versus JDK 18 (https://github.com/openjdk/jdk18).

[vnkozlov]

Yes, new PR have to be filed based on jdk18 repo pointed by Sandhya because we need to fix it in JDK 18. After integration the fix will be automatically pushed into JDK 19 (current repo).

[asgibbons]

I just created a PR (openjdk/jdk18#4) on the jdk-18 branch. Thanks for the heads-up,

[asgibbons]

/integrate

[openjdk]

@asgibbons This pull request has not yet been marked as ready for integration.

[TobiHartmann]

As Vladimir mentioned, the fix will be forward ported to JDK 19 automatically. This PR should be closed without integration.

[asgibbons]

Thank you, @TobiHartmann. Closing this PR now.