gs_main_set_lib_paths(gs_main_instance * minst)
{
    ref *paths = minst->lib_path.container.value.refs;
    int first_is_here =
        (r_size(&minst->lib_path.list) != 0 &&
         paths[0].value.bytes == (const byte *)gp_current_directory_name ? 1 : 0);
    int code = 0;
    int count = minst->lib_path.count;
    int i, have_rom_device = 0;

    if (minst->search_here_first) {
        if (!(first_is_here ||
              (r_size(&minst->lib_path.list) != 0 &&
               !bytes_compare((const byte *)gp_current_directory_name,
                              strlen(gp_current_directory_name),
                              paths[0].value.bytes,
                              r_size(&paths[0]))))
            ) {
            memmove(paths + 1, paths, count * sizeof(*paths));
            make_const_string(paths, avm_foreign | a_readonly,
                              strlen(gp_current_directory_name),
                              (const byte *)gp_current_directory_name);
        }
    } else {
        if (first_is_here)
            memmove(paths, paths + 1, count * sizeof(*paths));
    }
    r_set_size(&minst->lib_path.list,
               count + (minst->search_here_first ? 1 : 0));
    if (minst->lib_path.env != 0)
        code = file_path_add(minst, &minst->lib_path, minst->lib_path.env);
    /* now put the %rom%lib/ device path before the gs_lib_default_path on the list */
    for (i = 0; i < gx_io_device_table_count; i++) {
        const gx_io_device *iodev = gx_io_device_table[i];
        const char *dname = iodev->dname;

        if (dname && strlen(dname) == 5 && !memcmp("%rom%", dname, 5)) {
            struct stat pstat;
            /* gs_error_unregistered means no usable romfs is available */
            int code = iodev->procs.file_status((gx_io_device *)iodev, dname, &pstat);
            if (code != gs_error_unregistered){
                have_rom_device = 1;
            }
            break;
        }
    }
    if (have_rom_device && code >= 0) {
        code = file_path_add(minst, &minst->lib_path, "%rom%Resource/Init/");
        if (code < 0)
            return code;
        code = file_path_add(minst, &minst->lib_path, "%rom%lib/");
    }
    if (minst->lib_path.final != 0 && code >= 0)
        code = file_path_add(minst, &minst->lib_path, minst->lib_path.final);
    return code;
}

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.