Bring in security changes from the 9.2.5 release

Ran:
 - git format-patch v9.2.2..v9.2.5 --stdout > patchfile.patch
 - git checkout -b 9-2-5-security-patch origin/v9.2.2
 - git apply patchfile.patch
 - git commit
 - [Got the sha ref for the commit]
 - git checkout -b upstream-9-2-security master
 - git cherry-pick <SHA of the patchfile commit>
 - [Resolved conflicts]
 - git cherry-pick --continue

1 files changed, 59 insertions, 0 deletions

diff --git a/db/migrate/20170316163845_move_uploads_to_system_dir.rb b/db/migrate/20170316163845_move_uploads_to_system_dir.rb
new file mode 100644
index 00000000000..564ee10b5ab
--- /dev/null
+++ b/db/migrate/20170316163845_move_uploads_to_system_dir.rb
@@ -0,0 +1,59 @@
+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class MoveUploadsToSystemDir < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+  disable_ddl_transaction!
+
+  DOWNTIME = false
+  DIRECTORIES_TO_MOVE = %w(user project note group appearance).freeze
+
+  def up
+    return unless file_storage?
+
+    FileUtils.mkdir_p(new_upload_dir)
+
+    DIRECTORIES_TO_MOVE.each do |dir|
+      source = File.join(old_upload_dir, dir)
+      destination = File.join(new_upload_dir, dir)
+      next unless File.directory?(source)
+      next if File.directory?(destination)
+
+      say "Moving #{source} -> #{destination}"
+      FileUtils.mv(source, destination)
+      FileUtils.ln_s(destination, source)
+    end
+  end
+
+  def down
+    return unless file_storage?
+    return unless File.directory?(new_upload_dir)
+
+    DIRECTORIES_TO_MOVE.each do |dir|
+      source = File.join(new_upload_dir, dir)
+      destination = File.join(old_upload_dir, dir)
+      next unless File.directory?(source)
+      next if File.directory?(destination) && !File.symlink?(destination)
+
+      say "Moving #{source} -> #{destination}"
+      FileUtils.rm(destination) if File.symlink?(destination)
+      FileUtils.mv(source, destination)
+    end
+  end
+
+  def file_storage?
+    CarrierWave::Uploader::Base.storage == CarrierWave::Storage::File
+  end
+
+  def base_directory
+    Rails.root
+  end
+
+  def old_upload_dir
+    File.join(base_directory, "public", "uploads")
+  end
+
+  def new_upload_dir
+    File.join(base_directory, "public", "uploads", "system")
+  end
+end