--- a/src/http/ngx_http_request_body.c
+++ b/src/http/ngx_http_request_body.c
@@ -137,8 +137,9 @@ ngx_http_read_client_request_body(ngx_ht
     } else {
         /* set rb->rest */
 
-        if (ngx_http_request_body_filter(r, NULL) != NGX_OK) {
-            rc = NGX_HTTP_INTERNAL_SERVER_ERROR;
+        rc = ngx_http_request_body_filter(r, NULL);
+
+        if (rc != NGX_OK) {
             goto done;
         }
     }
@@ -305,6 +306,9 @@ ngx_http_do_read_client_request_body(ngx
                         return NGX_AGAIN;
                     }
 
+                    ngx_log_error(NGX_LOG_ALERT, c->log, 0,
+                                  "busy buffers after request body flush");
+
                     return NGX_HTTP_INTERNAL_SERVER_ERROR;
                 }
 
@@ -679,6 +683,7 @@ ngx_http_discarded_request_body_handler(
     if (rc == NGX_OK) {
         r->discard_body = 0;
         r->lingering_close = 0;
+        r->lingering_time = 0;
         ngx_http_finalize_request(r, NGX_DONE);
         return;
     }