[Python-checkins] cpython (3.3): cleanup overflowing handling in unicode_decode_call_errorhandler and
benjamin.peterson
python-checkins at python.org
Tue Sep 30 00:55:09 CEST 2014
https://hg.python.org/cpython/rev/3c67d19c624f
changeset: 92631:3c67d19c624f
branch: 3.3
parent: 92453:a4e0aee1a9b5
user: Benjamin Peterson <benjamin at python.org>
date: Mon Sep 29 18:18:57 2014 -0400
summary:
cleanup overflowing handling in unicode_decode_call_errorhandler and unicode_encode_ucs1 (closes #22518)
files:
Objects/unicodeobject.c | 76 +++++++++++++++++++++-------
1 files changed, 57 insertions(+), 19 deletions(-)
diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c
--- a/Objects/unicodeobject.c
+++ b/Objects/unicodeobject.c
@@ -4168,9 +4168,15 @@
at the new input position), so we won't have to check space
when there are no errors in the rest of the string) */
Py_ssize_t replen = PyUnicode_GET_LENGTH(repunicode);
- requiredsize = *outpos + replen + insize-newpos;
+ requiredsize = *outpos;
+ if (requiredsize > PY_SSIZE_T_MAX - replen)
+ goto overflow;
+ requiredsize += replen;
+ if (requiredsize > PY_SSIZE_T_MAX - (insize - newpos))
+ goto overflow;
+ requiredsize += insize - newpos;
if (requiredsize > outsize) {
- if (requiredsize<2*outsize)
+ if (outsize <= PY_SSIZE_T_MAX/2 && requiredsize < 2*outsize)
requiredsize = 2*outsize;
if (unicode_resize(output, requiredsize) < 0)
goto onError;
@@ -4191,9 +4197,15 @@
have+the replacement+the rest of the string (starting
at the new input position), so we won't have to check space
when there are no errors in the rest of the string) */
- requiredsize = *outpos + repwlen + insize-newpos;
+ requiredsize = *outpos;
+ if (requiredsize > PY_SSIZE_T_MAX - repwlen)
+ goto overflow;
+ requiredsize += repwlen;
+ if (requiredsize > PY_SSIZE_T_MAX - (insize - newpos))
+ goto overflow;
+ requiredsize += insize - newpos;
if (requiredsize > outsize) {
- if (requiredsize < 2*outsize)
+ if (outsize <= PY_SSIZE_T_MAX/2 && requiredsize < 2*outsize)
requiredsize = 2*outsize;
if (unicode_resize(output, requiredsize) < 0)
goto onError;
@@ -4210,6 +4222,11 @@
onError:
Py_XDECREF(restuple);
return res;
+
+ overflow:
+ PyErr_SetString(PyExc_OverflowError,
+ "decoded result is too long for a Python string");
+ goto onError;
}
/* --- UTF-7 Codec -------------------------------------------------------- */
@@ -6358,7 +6375,7 @@
Py_ssize_t collstart = pos;
Py_ssize_t collend = pos;
/* find all unecodable characters */
- while ((collend < size) && (PyUnicode_READ(kind, data, collend)>=limit))
+ while ((collend < size) && (PyUnicode_READ(kind, data, collend) >= limit))
++collend;
/* cache callback name lookup (if not done yet, i.e. it's the first error) */
if (known_errorHandler==-1) {
@@ -6378,36 +6395,43 @@
raise_encode_exception(&exc, encoding, unicode, collstart, collend, reason);
goto onError;
case 2: /* replace */
- while (collstart++<collend)
+ while (collstart++ < collend)
*str++ = '?'; /* fall through */
case 3: /* ignore */
pos = collend;
break;
case 4: /* xmlcharrefreplace */
respos = str - PyBytes_AS_STRING(res);
+ requiredsize = respos;
/* determine replacement size */
- for (i = collstart, repsize = 0; i < collend; ++i) {
+ for (i = collstart; i < collend; ++i) {
Py_UCS4 ch = PyUnicode_READ(kind, data, i);
+ Py_ssize_t incr;
if (ch < 10)
- repsize += 2+1+1;
+ incr = 2+1+1;
else if (ch < 100)
- repsize += 2+2+1;
+ incr = 2+2+1;
else if (ch < 1000)
- repsize += 2+3+1;
+ incr = 2+3+1;
else if (ch < 10000)
- repsize += 2+4+1;
+ incr = 2+4+1;
else if (ch < 100000)
- repsize += 2+5+1;
+ incr = 2+5+1;
else if (ch < 1000000)
- repsize += 2+6+1;
+ incr = 2+6+1;
else {
assert(ch <= MAX_UNICODE);
- repsize += 2+7+1;
+ incr = 2+7+1;
}
- }
- requiredsize = respos+repsize+(size-collend);
+ if (requiredsize > PY_SSIZE_T_MAX - incr)
+ goto overflow;
+ requiredsize += incr;
+ }
+ if (requiredsize > PY_SSIZE_T_MAX - (size - collend))
+ goto overflow;
+ requiredsize += size - collend;
if (requiredsize > ressize) {
- if (requiredsize<2*ressize)
+ if (ressize <= PY_SSIZE_T_MAX/2 && requiredsize < 2*ressize)
requiredsize = 2*ressize;
if (_PyBytes_Resize(&res, requiredsize))
goto onError;
@@ -6433,6 +6457,10 @@
if (repsize > 1) {
/* Make room for all additional bytes. */
respos = str - PyBytes_AS_STRING(res);
+ if (ressize > PY_SSIZE_T_MAX - repsize - 1) {
+ Py_DECREF(repunicode);
+ goto overflow;
+ }
if (_PyBytes_Resize(&res, ressize+repsize-1)) {
Py_DECREF(repunicode);
goto onError;
@@ -6451,9 +6479,15 @@
we won't have to check space for encodable characters) */
respos = str - PyBytes_AS_STRING(res);
repsize = PyUnicode_GET_LENGTH(repunicode);
- requiredsize = respos+repsize+(size-collend);
+ requiredsize = respos;
+ if (requiredsize > PY_SSIZE_T_MAX - repsize)
+ goto overflow;
+ requiredsize += repsize;
+ if (requiredsize > PY_SSIZE_T_MAX - (size - collend))
+ goto overflow;
+ requiredsize += size - collend;
if (requiredsize > ressize) {
- if (requiredsize<2*ressize)
+ if (ressize <= PY_SSIZE_T_MAX/2 && requiredsize < 2*ressize)
requiredsize = 2*ressize;
if (_PyBytes_Resize(&res, requiredsize)) {
Py_DECREF(repunicode);
@@ -6491,6 +6525,10 @@
Py_XDECREF(exc);
return res;
+ overflow:
+ PyErr_SetString(PyExc_OverflowError,
+ "encoded result is too long for a Python string");
+
onError:
Py_XDECREF(res);
Py_XDECREF(errorHandler);
--
Repository URL: https://hg.python.org/cpython
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