modules/proxy/ajp_utils.c:50: error: INTEGER_OVERFLOW_L2
  ([0, +oo] - 4):unsigned64 by call to `ajp_ilink_send`.

modules/proxy/ajp_utils.c:43:10: Call
41.     }
42. 
43.     rc = ajp_msg_serialize_cping(msg);
             ^
44.     if (rc != APR_SUCCESS) {
45.         ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01008)

modules/proxy/ajp_msg.c:632:15: Call
  630.     ajp_msg_reset(msg);
  631. 
  632.     if ((rc = ajp_msg_append_uint8(msg, CMD_AJP13_CPING)) != APR_SUCCESS)
                     ^
  633.         return rc;
  634. 

modules/proxy/ajp_msg.c:303:1: Parameter `*msg->buf`
    301.  * @return          APR_SUCCESS or error
    302.  */
    303. apr_status_t ajp_msg_append_uint8(ajp_msg_t *msg, apr_byte_t value)
         ^
    304. {
    305.     apr_size_t len = msg->len;

modules/proxy/ajp_utils.c:50:10: Call
48.     }
49. 
50.     rc = ajp_ilink_send(sock, msg);
             ^
51.     ajp_msg_log(r, msg, "ajp_handle_cping_cpong: ajp_ilink_send packet dump");
52.     if (rc != APR_SUCCESS) {

modules/proxy/ajp_link.c:21:1: Parameter `msg->len`
  19. APLOG_USE_MODULE(proxy_ajp);
  20. 
  21. apr_status_t ajp_ilink_send(apr_socket_t *sock, ajp_msg_t *msg)
      ^
  22. {
  23.     char         *buf;

modules/proxy/ajp_link.c:27:5: Call
  25.     apr_size_t   length;
  26. 
  27.     ajp_msg_end(msg);
          ^
  28. 
  29.     length = msg->len;

modules/proxy/ajp_msg.c:220:1: <LHS trace>
218.  * @return          APR_SUCCESS or error
219.  */
220. apr_status_t ajp_msg_end(ajp_msg_t *msg)
     ^
221. {
222.     apr_size_t len = msg->len - AJP_HEADER_LEN;

modules/proxy/ajp_msg.c:220:1: Parameter `msg->len`
    218.  * @return          APR_SUCCESS or error
    219.  */
    220. apr_status_t ajp_msg_end(ajp_msg_t *msg)
         ^
    221. {
    222.     apr_size_t len = msg->len - AJP_HEADER_LEN;

modules/proxy/ajp_msg.c:222:5: Binary operation: ([0, +oo] - 4):unsigned64 by call to `ajp_ilink_send` 
    220. apr_status_t ajp_msg_end(ajp_msg_t *msg)
    221. {
    222.     apr_size_t len = msg->len - AJP_HEADER_LEN;
             ^
    223. 
    224.     if (msg->server_side) {

apr_status_t ajp_msg_end(ajp_msg_t *msg)
{
    apr_size_t len = msg->len - AJP_HEADER_LEN;
    if (msg->server_side) {
        msg->buf[0] = 0x41;
        msg->buf[1] = 0x42;
    }
    else {
        msg->buf[0] = 0x12;
        msg->buf[1] = 0x34;
    }
    msg->buf[2] = (apr_byte_t)((len >> 8) & 0xFF);
    msg->buf[3] = (apr_byte_t)(len & 0xFF);
    return APR_SUCCESS;
}
['apr_status_t ajp_handle_cping_cpong(apr_socket_t *sock,\n                                    request_rec *r,\n                                    apr_interval_time_t timeout)\n{\n    ajp_msg_t *msg;\n    apr_status_t rc, rv;\n    apr_interval_time_t org;\n    apr_byte_t result;\n    ap_log_rerror(APLOG_MARK, APLOG_TRACE8, 0, r,\n                         "Into ajp_handle_cping_cpong");\n    rc = ajp_msg_create(r->pool, AJP_PING_PONG_SZ, &msg);\n    if (rc != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01007)\n               "ajp_handle_cping_cpong: ajp_msg_create failed");\n        return rc;\n    }\n    rc = ajp_msg_serialize_cping(msg);\n    if (rc != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01008)\n               "ajp_handle_cping_cpong: ajp_marshal_into_msgb failed");\n        return rc;\n    }\n    rc = ajp_ilink_send(sock, msg);\n    ajp_msg_log(r, msg, "ajp_handle_cping_cpong: ajp_ilink_send packet dump");\n    if (rc != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01009)\n               "ajp_handle_cping_cpong: ajp_ilink_send failed");\n        return rc;\n    }\n    rc = apr_socket_timeout_get(sock, &org);\n    if (rc != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01010)\n               "ajp_handle_cping_cpong: apr_socket_timeout_get failed");\n        return rc;\n    }\n    rc = apr_socket_timeout_set(sock, timeout);\n    if (rc != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01011)\n               "ajp_handle_cping_cpong: apr_socket_timeout_set failed");\n        return rc;\n    }\n    ajp_msg_reuse(msg);\n    rv = ajp_ilink_receive(sock, msg);\n    if (rv != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01012)\n               "ajp_handle_cping_cpong: ajp_ilink_receive failed");\n        goto cleanup;\n    }\n    ajp_msg_log(r, msg, "ajp_handle_cping_cpong: ajp_ilink_receive packet dump");\n    rv = ajp_msg_get_uint8(msg, &result);\n    if (rv != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01013)\n               "ajp_handle_cping_cpong: invalid CPONG message");\n        goto cleanup;\n    }\n    if (result != CMD_AJP13_CPONG) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01014)\n               "ajp_handle_cping_cpong: awaited CPONG, received %d ",\n               result);\n        rv = APR_EGENERAL;\n        goto cleanup;\n    }\ncleanup:\n    rc = apr_socket_timeout_set(sock, org);\n    if (rc != APR_SUCCESS) {\n        ap_log_rerror(APLOG_MARK, APLOG_ERR, 0, r, APLOGNO(01015)\n               "ajp_handle_cping_cpong: apr_socket_timeout_set failed");\n        return rc;\n    }\n    ap_log_rerror(APLOG_MARK, APLOG_TRACE8, 0, r,\n                         "ajp_handle_cping_cpong: Done");\n    return rv;\n}', 'apr_status_t ajp_msg_serialize_cping(ajp_msg_t *msg)\n{\n    apr_status_t rc;\n    ajp_msg_reset(msg);\n    if ((rc = ajp_msg_append_uint8(msg, CMD_AJP13_CPING)) != APR_SUCCESS)\n        return rc;\n    return APR_SUCCESS;\n}', 'apr_status_t ajp_msg_append_uint8(ajp_msg_t *msg, apr_byte_t value)\n{\n    apr_size_t len = msg->len;\n    if ((len + 1) > msg->max_size) {\n        return ajp_log_overflow(msg, "ajp_msg_append_uint8");\n    }\n    msg->buf[len] = value;\n    msg->len += 1;\n    return APR_SUCCESS;\n}', 'apr_status_t ajp_ilink_send(apr_socket_t *sock, ajp_msg_t *msg)\n{\n    char         *buf;\n    apr_status_t status;\n    apr_size_t   length;\n    ajp_msg_end(msg);\n    length = msg->len;\n    buf    = (char *)msg->buf;\n    do {\n        apr_size_t written = length;\n        status = apr_socket_send(sock, buf, &written);\n        if (status != APR_SUCCESS) {\n            ap_log_error(APLOG_MARK, APLOG_ERR, status, NULL, APLOGNO(01029)\n                          "ajp_ilink_send(): send failed");\n            return status;\n        }\n        length -= written;\n        buf    += written;\n    } while (length);\n    return APR_SUCCESS;\n}', 'apr_status_t ajp_msg_end(ajp_msg_t *msg)\n{\n    apr_size_t len = msg->len - AJP_HEADER_LEN;\n    if (msg->server_side) {\n        msg->buf[0] = 0x41;\n        msg->buf[1] = 0x42;\n    }\n    else {\n        msg->buf[0] = 0x12;\n        msg->buf[1] = 0x34;\n    }\n    msg->buf[2] = (apr_byte_t)((len >> 8) & 0xFF);\n    msg->buf[3] = (apr_byte_t)(len & 0xFF);\n    return APR_SUCCESS;\n}']