fix case when a host in fastcgi_pass, scgi_pass, and uwsgi_pass
is given by expression and refers to a defined upstream

src/http/modules/ngx_http_fastcgi_module.c

diff --git a/src/http/modules/ngx_http_fastcgi_module.c b/src/http/modules/ngx_http_fastcgi_module.c
index 12a1e81..12d5b1d 100644
--- a/src/http/modules/ngx_http_fastcgi_module.c
+++ b/src/http/modules/ngx_http_fastcgi_module.c
@@ -636,12 +636,6 @@
         return NGX_ERROR;
     }
 
-    if (url.no_port) {
-        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
-                      "no port in upstream \"%V\"", &url.url);
-        return NGX_ERROR;
-    }
-
     u = r->upstream;
 
     u->resolved = ngx_pcalloc(r->pool, sizeof(ngx_http_upstream_resolved_t));
@@ -658,6 +652,7 @@
     } else {
         u->resolved->host = url.host;
         u->resolved->port = url.port;
+        u->resolved->no_port = url.no_port;
     }
 
     return NGX_OK;

src/http/modules/ngx_http_scgi_module.c

diff --git a/src/http/modules/ngx_http_scgi_module.c b/src/http/modules/ngx_http_scgi_module.c
index d831e27..d745551 100644
--- a/src/http/modules/ngx_http_scgi_module.c
+++ b/src/http/modules/ngx_http_scgi_module.c
@@ -458,12 +458,6 @@
         return NGX_ERROR;
     }
 
-    if (url.no_port) {
-        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
-                      "no port in upstream \"%V\"", &url.url);
-        return NGX_ERROR;
-    }
-
     u = r->upstream;
 
     u->resolved = ngx_pcalloc(r->pool, sizeof(ngx_http_upstream_resolved_t));
@@ -480,6 +474,7 @@
     } else {
         u->resolved->host = url.host;
         u->resolved->port = url.port;
+        u->resolved->no_port = url.no_port;
     }
 
     return NGX_OK;

src/http/modules/ngx_http_uwsgi_module.c

diff --git a/src/http/modules/ngx_http_uwsgi_module.c b/src/http/modules/ngx_http_uwsgi_module.c
index a252913..cd3c7c1 100644
--- a/src/http/modules/ngx_http_uwsgi_module.c
+++ b/src/http/modules/ngx_http_uwsgi_module.c
@@ -491,12 +491,6 @@
         return NGX_ERROR;
     }
 
-    if (url.no_port) {
-        ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
-                      "no port in upstream \"%V\"", &url.url);
-        return NGX_ERROR;
-    }
-
     u = r->upstream;
 
     u->resolved = ngx_pcalloc(r->pool, sizeof(ngx_http_upstream_resolved_t));
@@ -513,6 +507,7 @@
     } else {
         u->resolved->host = url.host;
         u->resolved->port = url.port;
+        u->resolved->no_port = url.no_port;
     }
 
     return NGX_OK;

src/http/ngx_http_upstream.c

diff --git a/src/http/ngx_http_upstream.c b/src/http/ngx_http_upstream.c
index e8d8773..dc2d0c0 100644
--- a/src/http/ngx_http_upstream.c
+++ b/src/http/ngx_http_upstream.c
@@ -574,6 +574,14 @@
             }
         }
 
+        if (u->resolved->port == 0) {
+            ngx_log_error(NGX_LOG_ERR, r->connection->log, 0,
+                          "no port in upstream \"%V\"", host);
+            ngx_http_upstream_finalize_request(r, u,
+                                               NGX_HTTP_INTERNAL_SERVER_ERROR);
+            return;
+        }
+
         temp.name = *host;
 
         ctx = ngx_resolve_start(clcf->resolver, &temp);