The memory allocated in
tengine/modules/ngx_http_upstream_dynamic_module/ngx_http_upstream_dynamic_module.c

Line 249 in 9ecbaff

| | sin=ngx_pcalloc(r->pool, sizeof(structsockaddr_in)); |

may be too small for data size pc->socklen :

tengine/modules/ngx_http_upstream_dynamic_module/ngx_http_upstream_dynamic_module.c

Line 256 in 9ecbaff

| | ngx_memcpy(sin, pc->sockaddr, pc->socklen); |

A quick check is needed, somthing like:

if (pc->socklen > sizeof(struct sockaddr_in)) { 
  sin = ngx_pcalloc(r->pool, pc->socklen); 
} else {
  sin = ngx_pcalloc(r->pool, sizeof(struct sockaddr_in)); 
}