Created attachment 27332 [details]
a fix

The DEFLATE output filter contains this piece of code (as of server magic number 20110724)

    if (!ctx) {
        char *token;
        const char *encoding;

        /* Delay initialization until we have seen some data */
        e = APR_BRIGADE_FIRST(bb);
        while (1) {
            apr_status_t rc;
            if (e == APR_BRIGADE_SENTINEL(bb))
                return ap_pass_brigade(f->next, bb);
            if (APR_BUCKET_IS_EOS(e)) {
                ap_remove_output_filter(f);
                return ap_pass_brigade(f->next, bb);
            }
            if (APR_BUCKET_IS_METADATA(e))
                continue;

If there is no filter context yet and the passed brigade contains only a metadata bucket (a flush bucket for example) the "continue" statement is hit without changing "e". Hence, it enters an infinite loop.

The last "if" statement should read as follows to fix the problem:

            if (APR_BUCKET_IS_METADATA(e)) {
                e = APR_BUCKET_NEXT(e);
                continue;
            }