From 967f2a3052c2d22e31564b428a9aa8cc63dc2a9f Mon Sep 17 00:00:00 2001 From: kale-smoothie <34165060+kale-smoothie@users.noreply.github.com> Date: Mon, 27 Nov 2023 18:09:41 +0000 Subject: [PATCH] bpo-41422: Visit the Pickler's and Unpickler's memo in tp_traverse (GH-21664) Co-authored-by: Serhiy Storchaka --- .../2020-07-28-20-48-05.bpo-41422.iMwnMu.rst | 2 ++ Modules/_pickle.c | 15 +++++++++++++++ 2 files changed, 17 insertions(+) create mode 100644 Misc/NEWS.d/next/Library/2020-07-28-20-48-05.bpo-41422.iMwnMu.rst diff --git a/Misc/NEWS.d/next/Library/2020-07-28-20-48-05.bpo-41422.iMwnMu.rst b/Misc/NEWS.d/next/Library/2020-07-28-20-48-05.bpo-41422.iMwnMu.rst new file mode 100644 index 00000000000..8bde68f8f2a --- /dev/null +++ b/Misc/NEWS.d/next/Library/2020-07-28-20-48-05.bpo-41422.iMwnMu.rst @@ -0,0 +1,2 @@ +Fixed memory leaks of :class:`pickle.Pickler` and :class:`pickle.Unpickler` involving cyclic references via the +internal memo mapping. diff --git a/Modules/_pickle.c b/Modules/_pickle.c index a3cf34699ba..227e5378e42 100644 --- a/Modules/_pickle.c +++ b/Modules/_pickle.c @@ -4707,6 +4707,14 @@ Pickler_traverse(PicklerObject *self, visitproc visit, void *arg) Py_VISIT(self->fast_memo); Py_VISIT(self->reducer_override); Py_VISIT(self->buffer_callback); + PyMemoTable *memo = self->memo; + if (memo && memo->mt_table) { + Py_ssize_t i = memo->mt_allocated; + while (--i >= 0) { + Py_VISIT(memo->mt_table[i].me_key); + } + } + return 0; } @@ -7175,6 +7183,13 @@ Unpickler_traverse(UnpicklerObject *self, visitproc visit, void *arg) Py_VISIT(self->stack); Py_VISIT(self->pers_func); Py_VISIT(self->buffers); + PyObject **memo = self->memo; + if (memo) { + Py_ssize_t i = self->memo_size; + while (--i >= 0) { + Py_VISIT(memo[i]); + } + } return 0; }