Created attachment 395402 [details]
Patch v1

Comment on attachment 395402 [details]
Patch v1

So decoding always checks for both invalid hash table values for identifiers?

Comment on attachment 395402 [details]
Patch v1

View in context: https://bugs.webkit.org/attachment.cgi?id=395402&action=review

> Source/WebKit/ChangeLog:12
> +        - Remove MESSAGE_CHECK for `identifier` since decoding detects
> +          invalid values.

Both the empty and deleted values for identifiers as hash table keys are prohibited/checked?

Committed r259505: <https://trac.webkit.org/changeset/259505>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 395402 [details].

> > Source/WebKit/ChangeLog:12
> > +        - Remove MESSAGE_CHECK for `identifier` since decoding detects
> > +          invalid values.
> 
> Both the empty and deleted values for identifiers as hash table keys are
> prohibited/checked?

Looks like it:

    template<typename Decoder> static Optional<ObjectIdentifier> decode(Decoder& decoder)
    {
        Optional<uint64_t> identifier;
        decoder >> identifier;
        if (!identifier || !isValidIdentifier(*identifier))
            return WTF::nullopt;
        return ObjectIdentifier { *identifier };
    }

    static bool isValidIdentifier(uint64_t identifier) { return identifier && identifier != hashTableDeletedValue(); }