On Mon, 25 Sep 2023 18:12:32 GMT, Weijun Wang <wei...@openjdk.org> wrote:
> A different fix after https://github.com/openjdk/jdk/pull/14506 was closed. > > Still haven't made the attributes set immutable but at least it is populated > before an entry is added to `entries` and it will never be modified later. > > I tried the newly added `AttributesMultiThread.java` test hundreds of times > and only observed failures before this fix (~%2 failure rate). src/java.base/share/classes/sun/security/pkcs12/PKCS12KeyStore.java line 1270: > 1268: } > 1269: Entry entry = entries.get(alias.toLowerCase(Locale.ENGLISH)); > 1270: return Collections.unmodifiableSet(new > HashSet<>(entry.attributes)); I do not think this fix is correct. A call to `engineGetAttribute()` could observe an empty `HashSet` set by `populateAttributes`, but before the entry is populated. If we want to prevent that I believe we need a lock of some kind shared between `engineGetAttribute` and `populateAttributes`. Also the constructor of `HashSet` that takes a collection calls `HashSet.addAll()`, which loops over the provided collection. In a multi threaded context, if `populateAttributes` can run concurrently with `engineGetAttribute`, it is not impossible that this loop will get a `ConcurrentModificationException`, like before. Or am I missing something? ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/15909#discussion_r1337337639
