* error.c (exc_to_s, name_err_to_s, name_err_mesg_to_str): do not

  taint messages.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@37068 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

3 files changed, 56 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index afd5edd5cc..b6ae198ab1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Wed Oct  3 02:23:37 2012  Shugo Maeda  <shugo@ruby-lang.org>
+
+	* error.c (exc_to_s, name_err_to_s, name_err_mesg_to_str): do not
+	  taint messages.
+
 Tue Oct  2 16:47:06 2012  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* eval.c (identity_hash_new): hide internal hashes for refinements.
diff --git a/error.c b/error.c
index bb1ffa4e7d..5bfa2216eb 100644
--- a/error.c
+++ b/error.c
@@ -635,7 +635,6 @@ exc_to_s(VALUE exc)
 
     if (NIL_P(mesg)) return rb_class_name(CLASS_OF(exc));
     r = rb_String(mesg);
-    OBJ_INFECT(r, exc);
     return r;
 }
 
@@ -996,11 +995,7 @@ name_err_to_s(VALUE exc)
 
     if (NIL_P(mesg)) return rb_class_name(CLASS_OF(exc));
     StringValue(str);
-    if (str != mesg) {
-	rb_iv_set(exc, "mesg", mesg = str);
-    }
-    OBJ_INFECT(mesg, exc);
-    return mesg;
+    return str;
 }
 
 /*
@@ -1131,7 +1126,6 @@ name_err_mesg_to_str(VALUE obj)
 	args[2] = d;
 	mesg = rb_f_sprintf(NAME_ERR_MESG_COUNT, args);
     }
-    OBJ_INFECT(mesg, obj);
     return mesg;
 }
 
diff --git a/test/ruby/test_exception.rb b/test/ruby/test_exception.rb
index 93b24bbdd5..17492706ed 100644
--- a/test/ruby/test_exception.rb
+++ b/test/ruby/test_exception.rb
@@ -451,4 +451,54 @@ end.join
       end
     end
   end
+
+  def test_to_s_taintness_propagation
+    for exc in [Exception, NameError]
+      m = "abcdefg"
+      e = exc.new(m)
+      e.taint
+      s = e.to_s
+      assert_equal(false, m.tainted?,
+                   "#{exc}#to_s should not propagate taintness")
+      assert_equal(false, s.tainted?,
+                   "#{exc}#to_s should not propagate taintness")
+    end
+    
+    o = Object.new
+    def o.to_str
+      "foo"
+    end
+    o.taint
+    e = NameError.new(o)
+    s = e.to_s
+    assert_equal(false, s.tainted?)
+  end
+
+  def test_exception_to_s_should_not_propagate_untrustedness
+    favorite_lang = "Ruby"
+
+    for exc in [Exception, NameError]
+      assert_raise(SecurityError) do
+        lambda {
+          $SAFE = 4
+          exc.new(favorite_lang).to_s
+          favorite_lang.replace("Python")
+        }.call
+      end
+    end
+
+    assert_raise(SecurityError) do
+      lambda {
+        $SAFE = 4
+        o = Object.new
+        o.singleton_class.send(:define_method, :to_str) {
+          favorite_lang
+        }
+        NameError.new(o).to_s
+        favorite_lang.replace("Python")
+      }.call
+    end
+
+    assert_equal("Ruby", favorite_lang)
+  end
 end