int burl_normalize (buffer *b, buffer *t, int flags)
{
    int qs;

  #if defined(__WIN32) || defined(__CYGWIN__)
    /* Windows and Cygwin treat '\\' as '/' if '\\' is present in path;
     * convert to '/' for consistency before percent-encoding
     * normalization which will convert '\\' to "%5C" in the URL.
     * (Clients still should not be sending '\\' unencoded in requests.) */
    if (flags & HTTP_PARSEOPT_URL_NORMALIZE_PATH_BACKSLASH_TRANS) {
        for (char *p = b->ptr; *p != '?' && *p != '\0'; ++p) {
            if (*p == '\\') *p = '/';
        }
    }
  #endif

    qs = (flags & HTTP_PARSEOPT_URL_NORMALIZE_REQUIRED)
      ? burl_normalize_basic_required(b, t)
      : burl_normalize_basic_unreserved(b, t);
    if (-2 == qs) return -2;

    if (flags & HTTP_PARSEOPT_URL_NORMALIZE_CTRLS_REJECT) {
        if (burl_contains_ctrls(b)) return -2;
    }

    if (flags & (HTTP_PARSEOPT_URL_NORMALIZE_PATH_2F_DECODE
                |HTTP_PARSEOPT_URL_NORMALIZE_PATH_2F_REJECT)) {
        qs = burl_normalize_2F_to_slash(b, qs, flags);
        if (-2 == qs) return -2;
    }

    if (flags & (HTTP_PARSEOPT_URL_NORMALIZE_PATH_DOTSEG_REMOVE
                |HTTP_PARSEOPT_URL_NORMALIZE_PATH_DOTSEG_REJECT)) {
        qs = burl_normalize_path(b, t, qs, flags);
        if (-2 == qs) return -2;
    }

    if (flags & HTTP_PARSEOPT_URL_NORMALIZE_QUERY_20_PLUS) {
        if (qs >= 0) burl_normalize_qs20_to_plus(b, qs);
    }

    return qs;
}

The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.