* test/ruby/test_exception.rb (TestException::test_to_s_taintness_propagation):
	  Test for below.
	* error.c (exc_to_s): untainted strings can be tainted via
	  Exception#to_s, which enables attackers to overwrite sane strings.
	  Reported by: Yusuke Endoh <mame at tsg.ne.jp>.
	* error.c (name_err_to_s): ditto.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8_7@30911 b2dd03c8-39d4-4d8f-98ff-823fe69b080e