From 27f0a32d3db963efde7e3995036f3b4b72583cdf Mon Sep 17 00:00:00 2001
From: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Date: Mon, 11 Jul 2022 10:38:25 +0000
Subject: [PATCH 1/3] fix allocator and deallocator

---
 Lib/test/_test_multiprocessing.py    | 11 +++++++++++
 Modules/_multiprocessing/semaphore.c |  7 +++----
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/Lib/test/_test_multiprocessing.py b/Lib/test/_test_multiprocessing.py
index 75969975af35ba..4c4b9ac5323961 100644
--- a/Lib/test/_test_multiprocessing.py
+++ b/Lib/test/_test_multiprocessing.py
@@ -6020,3 +6020,14 @@ def tearDownModule():
 
     remote_globs['setUpModule'] = setUpModule
     remote_globs['tearDownModule'] = tearDownModule
+
+
+@unittest.skipIf(not hasattr(_multiprocessing, 'SemLock'), 'SemLock not available')
+class SemLockTests(unittest.TestCase):
+
+    def test_semlock_subclass(self):
+        class SemLock(_multiprocessing.SemLock):
+            pass
+        name = f'test_semlock_subclass-{os.getpid()}'
+        s = SemLock(1, 0, 10, name, 0)
+        _multiprocessing.sem_unlink(name)
diff --git a/Modules/_multiprocessing/semaphore.c b/Modules/_multiprocessing/semaphore.c
index 8607476aff10ff..af74ec47cfeaf2 100644
--- a/Modules/_multiprocessing/semaphore.c
+++ b/Modules/_multiprocessing/semaphore.c
@@ -454,9 +454,7 @@ static PyObject *
 newsemlockobject(PyTypeObject *type, SEM_HANDLE handle, int kind, int maxvalue,
                  char *name)
 {
-    SemLockObject *self;
-
-    self = PyObject_New(SemLockObject, type);
+    SemLockObject *self = (SemLockObject *)type->tp_alloc(type, 0);
     if (!self)
         return NULL;
     self->handle = handle;
@@ -573,7 +571,7 @@ semlock_dealloc(SemLockObject* self)
     if (self->handle != SEM_FAILED)
         SEM_CLOSE(self->handle);
     PyMem_Free(self->name);
-    PyObject_Free(self);
+    Py_TYPE(self)->tp_free((PyObject*)self);
 }
 
 /*[clinic input]
@@ -780,6 +778,7 @@ PyTypeObject _PyMp_SemLockType = {
     /* tp_init           */ 0,
     /* tp_alloc          */ 0,
     /* tp_new            */ _multiprocessing_SemLock,
+    .tp_free = PyObject_Free,
 };
 
 /*

From 699d81d637a81ad3a7f79897f75e395d8399e410 Mon Sep 17 00:00:00 2001
From: "blurb-it[bot]" <43283697+blurb-it[bot]@users.noreply.github.com>
Date: Mon, 11 Jul 2022 10:41:49 +0000
Subject: [PATCH 2/3] =?UTF-8?q?=F0=9F=93=9C=F0=9F=A4=96=20Added=20by=20blu?=
 =?UTF-8?q?rb=5Fit.?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../next/Library/2022-07-11-10-41-48.gh-issue-94736.EbsgeK.rst   | 1 +
 1 file changed, 1 insertion(+)
 create mode 100644 Misc/NEWS.d/next/Library/2022-07-11-10-41-48.gh-issue-94736.EbsgeK.rst

diff --git a/Misc/NEWS.d/next/Library/2022-07-11-10-41-48.gh-issue-94736.EbsgeK.rst b/Misc/NEWS.d/next/Library/2022-07-11-10-41-48.gh-issue-94736.EbsgeK.rst
new file mode 100644
index 00000000000000..3080672ecdfbb8
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-07-11-10-41-48.gh-issue-94736.EbsgeK.rst
@@ -0,0 +1 @@
+Fix crash when deallocating an instance of a subclass of ``_multiprocessing.SemLock``. Patch by Kumar Aditya.

From 4e2f2a06b1def284e8fd644aab2e20bfb6b9a474 Mon Sep 17 00:00:00 2001
From: Kumar Aditya <59607654+kumaraditya303@users.noreply.github.com>
Date: Mon, 11 Jul 2022 11:16:58 +0000
Subject: [PATCH 3/3] code review

---
 Modules/_multiprocessing/semaphore.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/Modules/_multiprocessing/semaphore.c b/Modules/_multiprocessing/semaphore.c
index af74ec47cfeaf2..f5fd3257f066a3 100644
--- a/Modules/_multiprocessing/semaphore.c
+++ b/Modules/_multiprocessing/semaphore.c
@@ -778,7 +778,6 @@ PyTypeObject _PyMp_SemLockType = {
     /* tp_init           */ 0,
     /* tp_alloc          */ 0,
     /* tp_new            */ _multiprocessing_SemLock,
-    .tp_free = PyObject_Free,
 };
 
 /*