Upstream-Status: Backport

Reference:http://bugs.python.org/issue14579

The utf-16 decoder in Python 3.1 through 3.3 does not update the
aligned_end variable after calling the unicode_decode_call_errorhandler
function, which allows remote attackers to obtain sensitive information
(process memory) or cause a denial of service (memory corruption and crash)
via unspecified vectors.

http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2012-2135
Signed-off-by: yanjun.zhu <yanjun.zhu@windriver.com>
diff -urpN a/Objects/unicodeobject.c b/Objects/unicodeobject.c
--- a/Objects/unicodeobject.c	2012-11-12 16:25:33.000000000 +0800
+++ b/Objects/unicodeobject.c	2012-11-12 16:26:22.000000000 +0800
@@ -2568,7 +2568,7 @@ PyUnicode_DecodeUTF16Stateful(const char
         }
 
         /* UTF-16 code pair: */
-        if (q >= e) {
+        if (e - q < 2) {
             errmsg = "unexpected end of data";
             startinpos = (((const char *)q)-2)-starts;
             endinpos = ((const char *)e)-starts;