diff --git a/Misc/NEWS b/Misc/NEWS index 6f9855ceee8..7ffe5217685 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -12,6 +12,11 @@ What's New in Python 2.4 alpha 1? Core and builtins ----------------- +- Fixed a bug in the cache of length-one Unicode strings that could + lead to a seg fault. The specific problem occurred when an earlier, + non-fatal error left an uninitialized Unicode object in the + freelist. + - The % formatting operator now supports '%F' which is equivalent to '%f'. This has always been documented but never implemented. diff --git a/Objects/unicodeobject.c b/Objects/unicodeobject.c index e2a16d95059..7adcd671c0f 100644 --- a/Objects/unicodeobject.c +++ b/Objects/unicodeobject.c @@ -132,7 +132,8 @@ int unicode_resize(register PyUnicodeObject *unicode, instead ! */ if (unicode == unicode_empty || (unicode->length == 1 && - unicode->str[0] < 256 && + /* XXX Is unicode->str[] always unsigned? */ + unicode->str[0] < 256U && unicode_latin1[unicode->str[0]] == unicode)) { PyErr_SetString(PyExc_SystemError, "can't resize shared unicode objects"); @@ -211,6 +212,10 @@ PyUnicodeObject *_PyUnicode_New(int length) PyErr_NoMemory(); goto onError; } + /* Initialize the first element to guard against cases where + the caller fails before initializing str. + */ + unicode->str[0] = 0; unicode->str[length] = 0; unicode->length = length; unicode->hash = -1; @@ -2527,7 +2532,7 @@ PyObject *PyUnicode_DecodeASCII(const char *s, else { startinpos = s-starts; endinpos = startinpos + 1; - outpos = p-PyUnicode_AS_UNICODE(v); + outpos = p - (Py_UNICODE *)PyUnicode_AS_UNICODE(v); if (unicode_decode_call_errorhandler( errors, &errorHandler, "ascii", "ordinal not in range(128)",