GNU LibreDWG 0.12.3.4163 through 0.12.3.4191 has a double-free in bit_chain_free (called from dwg_encode_MTEXT and dwg_encode_add_object).Referenceshttps://bugs.chromium.org/p/oss-fuzz/issues/detail?id=31724https://github.com/google/oss-fuzz-vulns/blob/main/vulns/libredwg/OSV-2021-495.yamlhttps://github.com/LibreDWG/libredwg/commit/9b6e0ff9ef02818df034fc42c3bd149a5ff89342
