1 files changed, 6 insertions, 1 deletions
diff --git a/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb b/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
index 3e8d64b0c6..040a83f7a6 100644
--- a/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
+++ b/actionpack/lib/action_dispatch/middleware/session/abstract_store.rb
@@ -121,7 +121,12 @@ module ActionDispatch
           unless options[:expire_after].nil?
             cookie[:expires] = Time.now + options.delete(:expire_after)
           end
-
+          
+          if options[:domain] == :all
+            top_level_domain = env["HTTP_HOST"].split('.')[-2..-1].join('.')
+            options[:domain] = ".#{top_level_domain}"
+          end
+          
           request = ActionDispatch::Request.new(env)
           set_cookie(request, cookie.merge!(options))
         end