RFR: 8306461: ObjectInputStream::readObject() should handle negative array sizes without throwing NegativeArraySizeExceptions [v3]

[Aleksey Shipilev]

On Wed, 26 Apr 2023 11:37:23 GMT, Volker Simonis <simonis at openjdk.org> wrote:

>> This issue was reported by: Yakov Shafranovich ([yakovsh at amazon.com](mailto:yakovsh at amazon.com))
>> 
>> Currently, `ObjectInputStream::readObject()` doesn't explicitly checks for a negative array length in the deserialization stream. Instead it calls `j.l.r.Array::newInstance(..)` with the negative length which results in a `NegativeArraySizeException`. NegativeArraySizeException is an unchecked exception which is neither declared in the signature of `ObjectInputStream::readObject()` nor mentioned in its API specification. It is therefore not obvious for users of `ObjectInputStream::readObject()` that they may have to handle `NegativeArraySizeException`s. It would therefor be better if a negative array length in the deserialization stream would be automatically wrapped in an `InvalidClassException` which is a checked exception (derived from `IOException` via `ObjectStreamException`) and declared in the signature of `ObjectInputStream::readObject()`.
>> 
>> If we do the negative array length check in `ObjectInputStream::readObject()` before filtering, this will then also fix `ObjectInputFilter.FilterInfo::arrayLength()` which is defined as:
>> 
>> Returns:
>> the non-negative number of array elements when deserializing an array of the class, otherwise -1
>> 
>> but currently returns a negative value if the array length is negative.
>
> Volker Simonis has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:
> 
>  - Merge branch 'master' into JDK-8306461
>  - Simplified exception message and fixed test to check the correct message
>  - Addresed review comments of @turbanoff, @shipilev and @RogerRiggs
>  - 8306461: ObjectInputStream::readObject() should handle negative array sizes without throwing NegativeArraySizeExceptions

Looks fine to me.

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Marked as reviewed by shade (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/13540#pullrequestreview-1401786764