From c3c9db89273fabc62ea1b48389d9a3000c1c03ae Mon Sep 17 00:00:00 2001
 From: Jay Bosamiya <jaybosamiya@gmail.com>
 Date: Sun, 18 Jun 2017 22:11:03 +0530
 Subject: [PATCH] [2.7] bpo-30657: Check & prevent integer overflow in
  PyString_DecodeEscape (#2174)
 
 ---
  Misc/ACKS              | 1 +
  Misc/NEWS              | 3 +++
  Objects/stringobject.c | 8 +++++++-
  3 files changed, 11 insertions(+), 1 deletion(-)
 
 diff --git a/Misc/ACKS b/Misc/ACKS
 index 95be42717a0..a411bc5ffc8 100644
 --- a/Misc/ACKS
 +++ b/Misc/ACKS
 @@ -152,6 +152,7 @@ Gregory Bond
  Matias Bordese
  Jonas Borgström
  Jurjen Bos
 +Jay Bosamiya
  Peter Bosch
  Dan Boswell
  Eric Bouck
 --- a/Objects/stringobject.c
 +++ b/Objects/stringobject.c
 @@ -612,7 +612,13 @@ PyObject *PyString_DecodeEscape(const char *s,
      char *p, *buf;
      const char *end;
      PyObject *v;
 -    Py_ssize_t newlen = recode_encoding ? 4*len:len;
 +    Py_ssize_t newlen;
 +    /* Check for integer overflow */
 +    if (recode_encoding && (len > PY_SSIZE_T_MAX / 4)) {
 +        PyErr_SetString(PyExc_OverflowError, "string is too large");
 +        return NULL;
 +    }
 +    newlen = recode_encoding ? 4*len:len;
      v = PyString_FromStringAndSize((char *)NULL, newlen);
      if (v == NULL)
          return NULL;