Part of bug #1523610: fix miscalculation of buffer length.
Also add a guard against NULL in converttuple and add a test case
(that previously would have crashed).
diff --git a/Python/getargs.c b/Python/getargs.c
index 1552790..508055e 100644
--- a/Python/getargs.c
+++ b/Python/getargs.c
@@ -351,8 +351,8 @@
"argument %d", iarg);
i = 0;
p += strlen(p);
- while (levels[i] > 0 && (int)(p-buf) < 220) {
- PyOS_snprintf(p, sizeof(buf) - (buf - p),
+ while (levels[i] > 0 && i < 32 && (int)(p-buf) < 220) {
+ PyOS_snprintf(p, sizeof(buf) - (p - buf),
", item %d", levels[i]-1);
p += strlen(p);
i++;
@@ -439,6 +439,13 @@
char *msg;
PyObject *item;
item = PySequence_GetItem(arg, i);
+ if (item == NULL) {
+ PyErr_Clear();
+ levels[0] = i+1;
+ levels[1] = 0;
+ strncpy(msgbuf, "is not retrievable", bufsize);
+ return msgbuf;
+ }
msg = convertitem(item, &format, p_va, flags, levels+1,
msgbuf, bufsize, freelist);
/* PySequence_GetItem calls tp->sq_item, which INCREFs */
@@ -1509,6 +1516,7 @@
else {
msg = skipitem(&format, p_va, flags);
if (msg) {
+ levels[0] = 0;
seterror(i+1, msg, levels, fname, message);
return cleanreturn(0, freelist);
}