Merge in release25-maint r60793:

 Added checks for integer overflows, contributed by Google. Some are
 only available if asserts are left in the code, in cases where they
 can't be triggered from Python code.

1 files changed, 7 insertions, 0 deletions

diff --git a/Modules/datetimemodule.c b/Modules/datetimemodule.c
index 3443b42baa..fcbd2e9ad2 100644
--- a/Modules/datetimemodule.c
+++ b/Modules/datetimemodule.c
@@ -1115,6 +1115,8 @@ format_utcoffset(char *buf, size_t buflen, const char *sep,
 	char sign;
 	int none;
 
+	assert(buflen >= 1);
+
 	offset = call_utcoffset(tzinfo, tzinfoarg, &none);
 	if (offset == -1 && PyErr_Occurred())
 		return -1;
@@ -1206,6 +1208,11 @@ wrap_strftime(PyObject *object, const char *format, size_t format_len,
 	 * a new format.  Since computing the replacements for those codes
 	 * is expensive, don't unless they're actually used.
 	 */
+	if (format_len > INT_MAX - 1) {
+		PyErr_NoMemory();
+		goto Done;
+	}
+
 	totalnew = format_len + 1;	/* realistic if no %z/%Z/%f */
 	newfmt = PyString_FromStringAndSize(NULL, totalnew);
 	if (newfmt == NULL) goto Done;