RFR: 8358537: (bf) JavaNioAccess::getBufferAddress bypasses direct buffer MemorySession state check [v2]

[Brian Burkhalter]

On Wed, 4 Jun 2025 17:09:07 GMT, Jorn Vernee <jvernee at openjdk.org> wrote:

> Discussed this with the rest of the Panama team. The way it works currently (without this PR) is how it's intended to work.

Thank you for the elucidation: that is very helpful.

Perhaps some comments need to be added in strategic places to clarify the situation to avoid similar confusion in the future? This PR arose out of #25531, in particular when [it was suggested](https://github.com/openjdk/jdk/pull/25531#discussion_r2115194676) to access the address of the direct buffer via `IOUtil.bufferAddress` which calls `JavaNioAccess.getBufferAddress`. A failure was expected for buffers created from shared `Arena`s but none occurred, and it looked like there had been an oversight in the buffer address access protocol.

-------------

PR Comment: https://git.openjdk.org/jdk/pull/25631#issuecomment-2940936917