Merge pull request #8027 from daenney/master

Atomic.rb assumes it may chown/chmod a file but doesn't handle the EPERM error.

Conflicts:
	activesupport/CHANGELOG.md
	guides/source/active_support_core_extensions.md

2 files changed, 14 insertions, 2 deletions

diff --git a/activesupport/CHANGELOG.md b/activesupport/CHANGELOG.md
index 76a232665f..c54e933fdc 100644
--- a/activesupport/CHANGELOG.md
+++ b/activesupport/CHANGELOG.md
@@ -1,3 +1,10 @@
+## Rails 3.2.10 (unreleased)
+
+*   Handle the possible Permission Denied errors atomic.rb might trigger due to
+    its chown and chmod calls. [Backport #8027]
+
+    *Daniele Sluijters*
+
 ## Rails 3.2.9 (unreleased)
 
 *   Add logger.push_tags and .pop_tags to complement logger.tagged:
diff --git a/activesupport/lib/active_support/core_ext/file/atomic.rb b/activesupport/lib/active_support/core_ext/file/atomic.rb
index fc3277f4d2..b0daf6db9e 100644
--- a/activesupport/lib/active_support/core_ext/file/atomic.rb
+++ b/activesupport/lib/active_support/core_ext/file/atomic.rb
@@ -36,7 +36,12 @@ class File
     FileUtils.mv(temp_file.path, file_name)
 
     # Set correct permissions on new file
-    chown(old_stat.uid, old_stat.gid, file_name)
-    chmod(old_stat.mode, file_name)
+    begin
+      chown(old_stat.uid, old_stat.gid, file_name)
+      # This operation will affect filesystem ACL's
+      chmod(old_stat.mode, file_name)
+    rescue Errno::EPERM
+      # Changing file ownership failed, moving on.
+    end
   end
 end