Skip to content

Restrict co_code to be under INT_MAX in codeobject #20628

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Jun 10, 2020
Merged

Restrict co_code to be under INT_MAX in codeobject #20628

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 8 additions & 0 deletions Objects/codeobject.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -166,6 +166,14 @@ PyCode_NewWithPosOnlyArgs(int argcount, int posonlyargcount, int kwonlyargcount,
return NULL;
}

/* Make sure that code is indexable with an int, this is
a long running assumption in ceval.c and many parts of
the interpreter. */
if (PyBytes_GET_SIZE(code) > INT_MAX) {
PyErr_SetString(PyExc_OverflowError, "co_code larger than INT_MAX");
return NULL;
}

/* Check for any inner or outer closure references */
n_cellvars = PyTuple_GET_SIZE(cellvars);
if (!n_cellvars && !PyTuple_GET_SIZE(freevars)) {
Expand Down
6 changes: 3 additions & 3 deletions Objects/frameobject.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -397,9 +397,9 @@ frame_setlineno(PyFrameObject *f, PyObject* p_new_lineno, void *Py_UNUSED(ignore
return -1;
}

int len = Py_SAFE_DOWNCAST(
PyBytes_GET_SIZE(f->f_code->co_code)/sizeof(_Py_CODEUNIT),
Py_ssize_t, int);
/* PyCode_NewWithPosOnlyArgs limits co_code to be under INT_MAX so this
* should never overflow. */
int len = (int)(PyBytes_GET_SIZE(f->f_code->co_code) / sizeof(_Py_CODEUNIT));
int *lines = marklines(f->f_code, len);
if (lines == NULL) {
return -1;
Expand Down