Issue #18137: Detect integer overflow on precision in float.__format__()
and complex.__format__().
diff --git a/Objects/stringlib/formatter.h b/Objects/stringlib/formatter.h
index 6b28224..fd22751 100644
--- a/Objects/stringlib/formatter.h
+++ b/Objects/stringlib/formatter.h
@@ -928,7 +928,7 @@
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;
STRINGLIB_CHAR type = format->type;
int add_pct = 0;
@@ -947,6 +947,12 @@
from a hard-code pseudo-locale */
LocaleInfo locale;
+ if (format->precision > INT_MAX) {
+ PyErr_SetString(PyExc_ValueError, "precision too big");
+ goto done;
+ }
+ precision = (int)format->precision;
+
/* Alternate is not allowed on floats. */
if (format->alternate) {
PyErr_SetString(PyExc_ValueError,
@@ -1078,7 +1084,7 @@
Py_ssize_t n_im_total;
int re_has_decimal;
int im_has_decimal;
- Py_ssize_t precision = format->precision;
+ Py_ssize_t precision;
Py_ssize_t default_precision = 6;
STRINGLIB_CHAR type = format->type;
STRINGLIB_CHAR *p_re;
@@ -1107,6 +1113,12 @@
from a hard-code pseudo-locale */
LocaleInfo locale;
+ if (format->precision > INT_MAX) {
+ PyErr_SetString(PyExc_ValueError, "precision too big");
+ goto done;
+ }
+ precision = (int)format->precision;
+
/* Alternate is not allowed on complex. */
if (format->alternate) {
PyErr_SetString(PyExc_ValueError,