From 11a7ff7eeefe763be9ade949e8f2a4a2d53f6129 Mon Sep 17 00:00:00 2001
From: Jakub Hrozek <jakub.hrozek@posteo.se>
Date: Oct 03 2018 19:02:06 +0000
Subject: Check negative return of PyList_Size


Merges:
https://pagure.io/libuser/issue/28

In case of an error, PyList_Size can return a negative value. We should
check that case, also to avoid compiler warnings like:

Error: COMPILER_WARNING: [#def41] [warning: defect not occurring in libuser-0.60-9.el7]
libuser-0.62/python/misc.c: scope_hint: In function 'libuser_admin_prompt'
libuser-0.62/python/misc.c:160:12: warning: argument 1 range [9223372036854775808, 18446744073709551615] exceeds maximum object size 9223372036854775807 [-Walloc-size-larger-than=]
/usr/include/glib-2.0/glib/glist.h:32: included_from: Included from here.
/usr/include/glib-2.0/glib/ghash.h:33: included_from: Included from here.
/usr/include/glib-2.0/glib.h:50: included_from: Included from here.
libuser-0.62/python/misc.c:25: included_from: Included from here.
/usr/include/glib-2.0/glib/gmem.h:96:10: note: in a call to allocation function 'g_malloc0_n' declared here

---

diff --git a/python/misc.c b/python/misc.c
index c4ce819..fcb0ccf 100644
--- a/python/misc.c
+++ b/python/misc.c
@@ -137,7 +137,12 @@ libuser_admin_prompt(struct libuser_admin *self, PyObject * args,
 		return NULL;
 	}
 	count = PyList_Size(list);
-	if (count > INT_MAX) {
+	if (count < 0) {
+		PyErr_SetString(PyExc_TypeError,
+				"prompt_list has no size; probably not a list");
+		DEBUG_EXIT;
+		return NULL;
+	} else if (count > INT_MAX) {
 		PyErr_SetString(PyExc_ValueError, "too many prompts");
 		DEBUG_EXIT;
 		return NULL;