3 files changed, 10 insertions, 3 deletions
diff --git a/activesupport/lib/active_support/callbacks.rb b/activesupport/lib/active_support/callbacks.rb
index bf560ec1fa..e6baddf5db 100644
--- a/activesupport/lib/active_support/callbacks.rb
+++ b/activesupport/lib/active_support/callbacks.rb
@@ -71,7 +71,7 @@ module ActiveSupport
     # halt the entire callback chain and display a deprecation message.
     # If false, callback chains will only be halted by calling +throw :abort+.
     # Defaults to +true+.
-    mattr_accessor(:halt_and_display_warning_on_return_false) { true }
+    mattr_accessor(:halt_and_display_warning_on_return_false, instance_writer: false) { true }
 
     # Runs the callbacks for the given event.
     #
@@ -742,7 +742,7 @@ module ActiveSupport
         options = names.extract_options!
 
         names.each do |name|
-          class_attribute "_#{name}_callbacks"
+          class_attribute "_#{name}_callbacks", instance_writer: false
           set_callbacks name, CallbackChain.new(name, options)
 
           module_eval <<-RUBY, __FILE__, __LINE__ + 1
diff --git a/activesupport/lib/active_support/gem_version.rb b/activesupport/lib/active_support/gem_version.rb
index 7790a9b2c0..3104d0e00f 100644
--- a/activesupport/lib/active_support/gem_version.rb
+++ b/activesupport/lib/active_support/gem_version.rb
@@ -8,7 +8,7 @@ module ActiveSupport
     MAJOR = 5
     MINOR = 0
     TINY  = 0
-    PRE   = "beta1"
+    PRE   = "beta1.1"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activesupport/lib/active_support/security_utils.rb b/activesupport/lib/active_support/security_utils.rb
index 64c4801179..9be8613ada 100644
--- a/activesupport/lib/active_support/security_utils.rb
+++ b/activesupport/lib/active_support/security_utils.rb
@@ -1,3 +1,5 @@
+require 'digest'
+
 module ActiveSupport
   module SecurityUtils
     # Constant time string comparison.
@@ -16,5 +18,10 @@ module ActiveSupport
       res == 0
     end
     module_function :secure_compare
+
+    def variable_size_secure_compare(a, b) # :nodoc:
+      secure_compare(::Digest::SHA256.hexdigest(a), ::Digest::SHA256.hexdigest(b))
+    end
+    module_function :variable_size_secure_compare
   end
 end