kernel32: CompareStringW should abort on the first nonmatching character to avoid an invalid memory access.

Signed-off-by: Dmitry Timoshkov <dmitry@baikal.ru>
Signed-off-by: Sebastian Lackner <sebastian@fds-team.de>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>

libs/wine/sortkey.c

@@ -223,6 +223,16 @@ static inline int compare_unicode_weights(int flags, const WCHAR *str1, int len1
         len1--;
         len2--;
     }
+    while (len1 && !*str1)
+    {
+        str1++;
+        len1--;
+    }
+    while (len2 && !*str2)
+    {
+        str2++;
+        len2--;
+    }
     return len1 - len2;
 }
 
@@ -272,6 +282,16 @@ static inline int compare_diacritic_weights(int flags, const WCHAR *str1, int le
         len1--;
         len2--;
     }
+    while (len1 && !*str1)
+    {
+        str1++;
+        len1--;
+    }
+    while (len2 && !*str2)
+    {
+        str2++;
+        len2--;
+    }
     return len1 - len2;
 }
 
@@ -321,23 +341,24 @@ static inline int compare_case_weights(int flags, const WCHAR *str1, int len1,
         len1--;
         len2--;
     }
+    while (len1 && !*str1)
+    {
+        str1++;
+        len1--;
+    }
+    while (len2 && !*str2)
+    {
+        str2++;
+        len2--;
+    }
     return len1 - len2;
 }
 
-static inline int real_length(const WCHAR *str, int len)
-{
-    while (len && !str[len - 1]) len--;
-    return len;
-}
-
 int wine_compare_string(int flags, const WCHAR *str1, int len1,
                         const WCHAR *str2, int len2)
 {
     int ret;
 
-    len1 = real_length(str1, len1);
-    len2 = real_length(str2, len2);
-
     ret = compare_unicode_weights(flags, str1, len1, str2, len2);
     if (!ret)
     {