From 2f084ecfe78472b6a1a6c8b07472672176d4f848 Mon Sep 17 00:00:00 2001 From: Victor Stinner Date: Sun, 23 Jun 2013 14:54:30 +0200 Subject: Issue #18137: Detect integer overflow on precision in float.__format__() and complex.__format__(). --- Lib/test/test_format.py | 17 +++++++++++++++++ Misc/NEWS | 3 +++ Python/formatter_unicode.c | 16 ++++++++++++++-- 3 files changed, 34 insertions(+), 2 deletions(-) diff --git a/Lib/test/test_format.py b/Lib/test/test_format.py index f8f5420..bd159f5 100644 --- a/Lib/test/test_format.py +++ b/Lib/test/test_format.py @@ -312,6 +312,23 @@ class FormatTest(unittest.TestCase): def test_main(): support.run_unittest(FormatTest) + def test_precision(self): + INT_MAX = 2147483647 + + f = 1.2 + self.assertEqual(format(f, ".0f"), "1") + self.assertEqual(format(f, ".3f"), "1.200") + with self.assertRaises(ValueError) as cm: + format(f, ".%sf" % (INT_MAX + 1)) + self.assertEqual(str(cm.exception), "precision too big") + + c = complex(f) + self.assertEqual(format(f, ".0f"), "1") + self.assertEqual(format(f, ".3f"), "1.200") + with self.assertRaises(ValueError) as cm: + format(f, ".%sf" % (INT_MAX + 1)) + self.assertEqual(str(cm.exception), "precision too big") + if __name__ == "__main__": unittest.main() diff --git a/Misc/NEWS b/Misc/NEWS index 59e915c..04b5e41 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -12,6 +12,9 @@ What's New in Python 3.3.3 release candidate 1? Core and Builtins ----------------- +- Issue #18137: Detect integer overflow on precision in float.__format__() + and complex.__format__(). + - Issue #18183: Fix various unicode operations on strings with large unicode codepoints. diff --git a/Python/formatter_unicode.c b/Python/formatter_unicode.c index 17eb978..2fe446a 100644 --- a/Python/formatter_unicode.c +++ b/Python/formatter_unicode.c @@ -977,7 +977,7 @@ format_float_internal(PyObject *value, Py_ssize_t n_total; int has_decimal; double val; - Py_ssize_t precision = format->precision; + Py_ssize_t precision; Py_ssize_t default_precision = 6; Py_UCS4 type = format->type; int add_pct = 0; @@ -994,6 +994,12 @@ format_float_internal(PyObject *value, from a hard-code pseudo-locale */ LocaleInfo locale = STATIC_LOCALE_INFO_INIT; + if (format->precision > INT_MAX) { + PyErr_SetString(PyExc_ValueError, "precision too big"); + goto done; + } + precision = (int)format->precision; + if (format->alternate) flags |= Py_DTSF_ALT; @@ -1127,7 +1133,7 @@ format_complex_internal(PyObject *value, Py_ssize_t n_im_total; int re_has_decimal; int im_has_decimal; - Py_ssize_t precision = format->precision; + int precision; Py_ssize_t default_precision = 6; Py_UCS4 type = format->type; Py_ssize_t i_re; @@ -1155,6 +1161,12 @@ format_complex_internal(PyObject *value, from a hard-code pseudo-locale */ LocaleInfo locale = STATIC_LOCALE_INFO_INIT; + if (format->precision > INT_MAX) { + PyErr_SetString(PyExc_ValueError, "precision too big"); + goto done; + } + precision = (int)format->precision; + /* Zero padding is not allowed. */ if (format->fill_char == '0') { PyErr_SetString(PyExc_ValueError, -- cgit v0.12