Fix race condition in content length

1 files changed, 5 insertions, 1 deletions

diff --git a/lib/rack/content_length.rb b/lib/rack/content_length.rb
index 634bdc41..71bc919b 100644
--- a/lib/rack/content_length.rb
+++ b/lib/rack/content_length.rb
@@ -1,4 +1,5 @@
 require 'rack/utils'
+require 'rack/body_proxy'
 
 module Rack
 
@@ -22,7 +23,10 @@ module Rack
         obody = body
         body, length = [], 0
         obody.each { |part| body << part; length += bytesize(part) }
-        obody.close if obody.respond_to?(:close)
+
+        body = BodyProxy.new(body) do
+          obody.close if obody.respond_to?(:close)
+        end
 
         headers['Content-Length'] = length.to_s
       end