bpo-31286, bpo-30024: Fixed stack usage in absolute imports with (#3217)
binding a submodule to a name.
diff --git a/Lib/test/test_import/__init__.py b/Lib/test/test_import/__init__.py
index 1b04de2..ddef27d 100644
--- a/Lib/test/test_import/__init__.py
+++ b/Lib/test/test_import/__init__.py
@@ -237,6 +237,23 @@
import test.support as y
self.assertIs(y, test.support, y.__name__)
+ def test_issue31286(self):
+ # import in a 'finally' block resulted in SystemError
+ try:
+ x = ...
+ finally:
+ import test.support.script_helper as x
+
+ # import in a 'while' loop resulted in stack overflow
+ i = 0
+ while i < 10:
+ import test.support.script_helper as x
+ i += 1
+
+ # import in a 'for' loop resulted in segmentation fault
+ for i in range(2):
+ import test.support.script_helper as x
+
def test_failing_reload(self):
# A failing reload should leave the module object in sys.modules.
source = TESTFN + os.extsep + "py"
diff --git a/Python/compile.c b/Python/compile.c
index 78e797a..e547c2f 100644
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -2673,28 +2673,34 @@
If there is a dot in name, we need to split it and emit a
IMPORT_FROM for each name.
*/
- Py_ssize_t dot = PyUnicode_FindChar(name, '.', 0,
- PyUnicode_GET_LENGTH(name), 1);
+ Py_ssize_t len = PyUnicode_GET_LENGTH(name);
+ Py_ssize_t dot = PyUnicode_FindChar(name, '.', 0, len, 1);
if (dot == -2)
return 0;
if (dot != -1) {
/* Consume the base module name to get the first attribute */
- Py_ssize_t pos = dot + 1;
- while (dot != -1) {
+ while (1) {
+ Py_ssize_t pos = dot + 1;
PyObject *attr;
- dot = PyUnicode_FindChar(name, '.', pos,
- PyUnicode_GET_LENGTH(name), 1);
+ dot = PyUnicode_FindChar(name, '.', pos, len, 1);
if (dot == -2)
return 0;
- attr = PyUnicode_Substring(name, pos,
- (dot != -1) ? dot :
- PyUnicode_GET_LENGTH(name));
+ attr = PyUnicode_Substring(name, pos, (dot != -1) ? dot : len);
if (!attr)
return 0;
ADDOP_O(c, IMPORT_FROM, attr, names);
Py_DECREF(attr);
- pos = dot + 1;
+ if (dot == -1) {
+ break;
+ }
+ ADDOP(c, ROT_TWO);
+ ADDOP(c, POP_TOP);
}
+ if (!compiler_nameop(c, asname, Store)) {
+ return 0;
+ }
+ ADDOP(c, POP_TOP);
+ return 1;
}
return compiler_nameop(c, asname, Store);
}