RFR: 8277489: Rewrite JAAS UnixLoginModule with FFM [v5]

[Martin Doerr]

On Mon, 5 Jan 2026 21:30:54 GMT, Weijun Wang <weijun at openjdk.org> wrote:

>> FWIW there is an issue and ML discussion relating to extension of arguments with respect to `ValueLayout`: https://bugs.openjdk.org/browse/JDK-8336664
>
> \What happens if you create a user on AIX with a uid bigger than 2^31 and call `getpwuid_r` on it (by hardcoding `tmpUid` as a negative number)?

I haven't tried (not my machine), but it's undefined behavior. There's no guarantee that `getpwuid_r` does what we expect. We should never use undefined behavior. Also note that not only AIX is affected.

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PR Review Comment: https://git.openjdk.org/jdk/pull/28931#discussion_r2668116234