win32ole.c: check argument type

* ext/win32ole/win32ole.c (ole_vstr2wc): check argument type, vstr
  must be a String here.  reported by Marcin 'Icewall' Noga of
  Cisco Talos.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@53074 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

ChangeLog

@@ -1,3 +1,9 @@
+Sun Dec 13 18:19:20 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* ext/win32ole/win32ole.c (ole_vstr2wc): check argument type, vstr
+	  must be a String here.  reported by Marcin 'Icewall' Noga of
+	  Cisco Talos.
+
 Sun Dec 13 16:41:01 2015  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* configure.in (BOOTSTRAPRUBY): make BASERUBY full path before

ext/win32ole/win32ole.c

@@ -860,6 +860,11 @@ ole_vstr2wc(VALUE vstr)
     LPWSTR pw;
     st_data_t data;
     struct st_table *tbl = DATA_PTR(enc2cp_hash);
+
+    /* do not type-conversion here to prevent from other arguments
+     * changing (if exist) */
+    Check_Type(vstr, T_STRING);
+
     enc = rb_enc_get(vstr);
 
     if (st_lookup(tbl, (VALUE)enc | FIXNUM_FLAG, &data)) {

test/win32ole/test_win32ole.rb

@@ -312,6 +312,9 @@ if defined?(WIN32OLE)
       assert_raise(ArgumentError) {
         shell.ole_query_interface
       }
+      assert_raise(TypeError) {
+        shell.ole_query_interface(0x11223344)
+      }
       shell2 = shell.ole_query_interface('{A4C6892C-3BA9-11D2-9DEA-00C04FB16162}')
       assert_instance_of(WIN32OLE, shell2)
     end