--- src/os/unix/ngx_files.c
 +++ src/os/unix/ngx_files.c
 @@ -356,6 +356,11 @@
      n = 0;
  
      for ( /* void */ ; cl; cl = cl->next) {
 +
 +        if (ngx_buf_special(cl->buf)) {
 +            continue;
 +        }
 +
          size = cl->buf->last - cl->buf->pos;
  
          if (prev == cl->buf->pos) {