[PATCH 1/2] ntdll: Fix RtlUTF8ToUnicodeN for expected output ending with a surrogate pair that doesn't fit.

[Alfred Agrell]

From: Alfred Agrell

---
 dlls/ntdll/locale_private.h | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/dlls/ntdll/locale_private.h b/dlls/ntdll/locale_private.h
index 40d6ab0004d..3f82129790a 100644
--- a/dlls/ntdll/locale_private.h
+++ b/dlls/ntdll/locale_private.h
@@ -443,7 +443,11 @@ static inline NTSTATUS utf8_mbstowcs( WCHAR *dst, unsigned int dstlen, unsigned
         {
             res -= 0x10000;
             *dst++ = 0xd800 | (res >> 10);
-            if (dst == dstend) break;
+            if (dst == dstend)
+            {
+                status = STATUS_BUFFER_TOO_SMALL;
+                break;
+            }
             *dst++ = 0xdc00 | (res & 0x3ff);
         }
         else