2 files changed, 4 insertions, 1 deletions
diff --git a/actionpack/lib/action_controller/request.rb b/actionpack/lib/action_controller/request.rb
index 68a5ea3701..e9a2e797dd 100755
--- a/actionpack/lib/action_controller/request.rb
+++ b/actionpack/lib/action_controller/request.rb
@@ -598,6 +598,7 @@ module ActionController
           end
           raise EOFError, "bad boundary end of body part" unless boundary_end=~/--/
 
+          body.rewind if body.respond_to?(:rewind)
           params
         end
     end
diff --git a/actionpack/test/controller/request_test.rb b/actionpack/test/controller/request_test.rb
index 1bb01ffd00..c62b2a6ec7 100644
--- a/actionpack/test/controller/request_test.rb
+++ b/actionpack/test/controller/request_test.rb
@@ -719,7 +719,9 @@ class MultipartRequestParameterParsingTest < Test::Unit::TestCase
   private
     def process(name)
       File.open(File.join(FIXTURE_PATH, name), 'rb') do |file|
-        ActionController::AbstractRequest.parse_multipart_form_parameters(file, 'AaB03x', file.stat.size, {})
+        params = ActionController::AbstractRequest.parse_multipart_form_parameters(file, 'AaB03x', file.stat.size, {})
+        assert_equal 0, file.pos  # file was rewound after reading
+        params
       end
     end
 end