Ruby on Rails Permission denied sessionsエラー

【環境】
linux Ruby on Rails fcgi

【現象】
ページ表示に

We're sorry, but something went wrong.

We've been notified about this issue and we'll take a look at it shortly.

とエラーがでて

../log/development.logをみると
例： tail -f development.log

Permission denied - /XXXXXXX/public/../config/../tmp/sessions//ruby_sess.96d5cabf36d3d426
/usr/lib/ruby/1.8/pstore.rb:290:in `initialize'
/usr/lib/ruby/1.8/pstore.rb:290:in `open'
/usr/lib/ruby/1.8/pstore.rb:290:in `transaction'
/usr/lib/ruby/1.8/cgi/session/pstore.rb:62:in `initialize'
/usr/lib/ruby/1.8/cgi/session.rb:273:in `new'
/usr/lib/ruby/1.8/cgi/session.rb:273:in `initialize'

となっていた


【原因】
../public/../config/../tmp/sessions　のパーミッションの問題

【対応】
とりあえず
chmod 777 ../public/../config/../tmp/sessions
でパーミッションフルにして対応