Thomas Faller : vbscript: Fix for unchecked memory access.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 06dfe8fcd6e82ceb4adf4cee576e676f59d24778
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=06dfe8fcd6e82ceb4adf4cee57...

Author: Thomas Faller <tfaller1(a)gmx.de>
Date:   Sat May 23 18:58:00 2015 +0200

vbscript: Fix for unchecked memory access.

---

 dlls/vbscript/global.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/dlls/vbscript/global.c b/dlls/vbscript/global.c
index 1a20527..129d6ce 100644
--- a/dlls/vbscript/global.c
+++ b/dlls/vbscript/global.c
@@ -1827,7 +1827,7 @@ static HRESULT Global_InStrRev(vbdisp_t *This, VARIANT *args, unsigned args_cnt,
 
     assert(2 <= args_cnt && args_cnt <= 4);
 
-    if(V_VT(args) == VT_NULL || V_VT(args+1) == VT_NULL || V_VT(args+2) == VT_NULL)
+    if(V_VT(args) == VT_NULL || V_VT(args+1) == VT_NULL || (args_cnt > 2 && V_VT(args+2) == VT_NULL))
         return MAKE_VBSERROR(VBSE_ILLEGAL_NULL_USE);
 
     hres = to_string(args, &str1);