always transcode the file to utf-8

people may be passing filenames to the constructor that are not utf-8,
but they will assome that calling `original_filename` returns utf-8
(because that's what it used to do).

1 files changed, 1 insertions, 0 deletions

diff --git a/actionpack/lib/action_dispatch/http/upload.rb b/actionpack/lib/action_dispatch/http/upload.rb
index 538bcfdcd7..540e11a4a0 100644
--- a/actionpack/lib/action_dispatch/http/upload.rb
+++ b/actionpack/lib/action_dispatch/http/upload.rb
@@ -28,6 +28,7 @@ module ActionDispatch
         raise(ArgumentError, ':tempfile is required') unless @tempfile
 
         @original_filename = hash[:filename]
+        @original_filename &&= @original_filename.encode "UTF-8"
         @content_type      = hash[:type]
         @headers           = hash[:head]
       end