Check if file exists on root path traversal [closes GH-182]

CHANGELOG.md

@@ -1,6 +1,6 @@
 ## 0.6.6 (unreleased)
 
-
+  - Fix potential infinite loop with root path if bad CWD is given to environment.
 
 ## 0.6.5 (October 8, 2010)
 

lib/vagrant/environment.rb

@@ -243,7 +243,7 @@ module Vagrant
 
       root_finder = lambda do |path|
         return path if File.exist?(File.join(path.to_s, ROOTFILE_NAME))
-        return nil if path.root?
+        return nil if path.root? || !File.exist?(path)
         root_finder.call(path.parent)
       end
 

test/vagrant/environment_test.rb

@@ -242,6 +242,7 @@ class EnvironmentTest < Test::Unit::TestCase
       search_seq = sequence("search_seq")
       paths.each do |path|
         File.expects(:exist?).with(path.join(@klass::ROOTFILE_NAME).to_s).returns(false).in_sequence(search_seq)
+        File.expects(:exist?).with(path).returns(true).in_sequence(search_seq) if !path.root?
       end
 
       assert !@klass.new(:cwd => paths.first).root_path
@@ -254,6 +255,10 @@ class EnvironmentTest < Test::Unit::TestCase
       assert_equal path, @klass.new(:cwd => path).root_path
     end
 
+    should "not infinite loop on relative paths" do
+      assert @klass.new(:cwd => "../test").root_path.nil?
+    end
+
     should "only load the root path once" do
       env = @klass.new
       File.expects(:exist?).with(env.cwd.join(@klass::ROOTFILE_NAME).to_s).returns(true).once