Piotr Caban : msvcrt: Return error if last known character is further in the string then current character.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 9f532321d0bb88fc1bd321de44c89c64122acceb
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=9f532321d0bb88fc1bd321de44...

Author: Piotr Caban 
Date:   Mon Dec 21 11:22:55 2015 +0100

msvcrt: Return error if last known character is further in the string then current character.

Signed-off-by: Piotr Caban 
Signed-off-by: Alexandre Julliard

---

dlls/msvcrt/mbcs.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/dlls/msvcrt/mbcs.c b/dlls/msvcrt/mbcs.c
index e7adaad..56945bb 100644
--- a/dlls/msvcrt/mbcs.c
+++ b/dlls/msvcrt/mbcs.c
@@ -520,6 +520,9 @@ unsigned int CDECL _mbcjmstojis(unsigned int c)
  */
 unsigned char* CDECL _mbsdec(const unsigned char* start, const unsigned char* cur)
 {
+  if(start >= cur)
+    return NULL;
+
   if(get_mbcinfo()->ismbcodepage)
     return (unsigned char *)(_ismbstrail(start,cur-1) ? cur - 2 : cur -1);