From f08bf726d3038f062dd7485614d1ea85d952f121 Mon Sep 17 00:00:00 2001 From: Edouard CHIN Date: Thu, 11 Jul 2019 16:25:40 +0200 Subject: Return a copy of the cache entry when local_cache exists: - When the local cache exists (during the request lifecycle), the entry returned from the LocalStore is passed as a reference which means mutable object can accidentaly get modified. This behaviour seems unnecessarily unsafe and is prone to issues like it happened in our application. This patch dup the `Entry` returned from the cache and dup it's internal value. --- activesupport/lib/active_support/cache/strategy/local_cache.rb | 5 ++++- activesupport/test/cache/behaviors/local_cache_behavior.rb | 9 +++++++++ 2 files changed, 13 insertions(+), 1 deletion(-) (limited to 'activesupport') diff --git a/activesupport/lib/active_support/cache/strategy/local_cache.rb b/activesupport/lib/active_support/cache/strategy/local_cache.rb index 39b32fc7f6..4ca084163b 100644 --- a/activesupport/lib/active_support/cache/strategy/local_cache.rb +++ b/activesupport/lib/active_support/cache/strategy/local_cache.rb @@ -75,7 +75,10 @@ module ActiveSupport end def fetch_entry(key, options = nil) # :nodoc: - @data.fetch(key) { @data[key] = yield } + entry = @data.fetch(key) { @data[key] = yield } + dup_entry = entry.dup + dup_entry&.dup_value! + dup_entry end end diff --git a/activesupport/test/cache/behaviors/local_cache_behavior.rb b/activesupport/test/cache/behaviors/local_cache_behavior.rb index baa38ba6ac..6f5d53c190 100644 --- a/activesupport/test/cache/behaviors/local_cache_behavior.rb +++ b/activesupport/test/cache/behaviors/local_cache_behavior.rb @@ -46,6 +46,15 @@ module LocalCacheBehavior end end + def test_local_cache_of_read_returns_a_copy_of_the_entry + @cache.with_local_cache do + @cache.write(:foo, type: "bar") + value = @cache.read(:foo) + assert_equal("bar", value.delete(:type)) + assert_equal({ type: "bar" }, @cache.read(:foo)) + end + end + def test_local_cache_of_read @cache.write("foo", "bar") @cache.with_local_cache do -- cgit v1.2.3