Issue #6083: Fix multiple segmentation faults occured when PyArg_ParseTuple
parses nested mutating sequence.
diff --git a/Modules/_ctypes/_ctypes.c b/Modules/_ctypes/_ctypes.c
index 73ab2fd..e4e237e 100644
--- a/Modules/_ctypes/_ctypes.c
+++ b/Modules/_ctypes/_ctypes.c
@@ -3184,23 +3184,37 @@
 {
     char *name;
     int (* address)(void);
+    PyObject *ftuple;
     PyObject *dll;
     PyObject *obj;
     PyCFuncPtrObject *self;
     void *handle;
     PyObject *paramflags = NULL;
 
-    if (!PyArg_ParseTuple(args, "(O&O)|O", _get_name, &name, &dll, &paramflags))
+    if (!PyArg_ParseTuple(args, "O|O", &ftuple, &paramflags))
         return NULL;
     if (paramflags == Py_None)
         paramflags = NULL;
 
-    obj = PyObject_GetAttrString(dll, "_handle");
-    if (!obj)
+    ftuple = PySequence_Tuple(ftuple);
+    if (!ftuple)
+        /* Here ftuple is a borrowed reference */
         return NULL;
+
+    if (!PyArg_ParseTuple(ftuple, "O&O", _get_name, &name, &dll)) {
+        Py_DECREF(ftuple);
+        return NULL;
+    }
+
+    obj = PyObject_GetAttrString(dll, "_handle");
+    if (!obj) {
+        Py_DECREF(ftuple);
+        return NULL;
+    }
     if (!PyLong_Check(obj)) {
         PyErr_SetString(PyExc_TypeError,
                         "the _handle attribute of the second argument must be an integer");
+        Py_DECREF(ftuple);
         Py_DECREF(obj);
         return NULL;
     }
@@ -3209,6 +3223,7 @@
     if (PyErr_Occurred()) {
         PyErr_SetString(PyExc_ValueError,
                         "could not convert the _handle attribute to a pointer");
+        Py_DECREF(ftuple);
         return NULL;
     }
 
@@ -3223,6 +3238,7 @@
             PyErr_Format(PyExc_AttributeError,
                          "function ordinal %d not found",
                          (WORD)(size_t)name);
+        Py_DECREF(ftuple);
         return NULL;
     }
 #else
@@ -3236,9 +3252,12 @@
 #else
         PyErr_SetString(PyExc_AttributeError, ctypes_dlerror());
 #endif
+        Py_DECREF(ftuple);
         return NULL;
     }
 #endif
+    Py_INCREF(dll); /* for KeepRef */
+    Py_DECREF(ftuple);
     if (!_validate_paramflags(type, paramflags))
         return NULL;
 
@@ -3251,7 +3270,6 @@
 
     *(void **)self->b_ptr = address;
 
-    Py_INCREF((PyObject *)dll); /* for KeepRef */
     if (-1 == KeepRef((CDataObject *)self, 0, dll)) {
         Py_DECREF((PyObject *)self);
         return NULL;
diff --git a/Modules/_functoolsmodule.c b/Modules/_functoolsmodule.c
index d8a283b..a0ea3ab 100644
--- a/Modules/_functoolsmodule.c
+++ b/Modules/_functoolsmodule.c
@@ -254,10 +254,10 @@
 }
 
 static PyObject *
-partial_setstate(partialobject *pto, PyObject *args)
+partial_setstate(partialobject *pto, PyObject *state)
 {
     PyObject *fn, *fnargs, *kw, *dict;
-    if (!PyArg_ParseTuple(args, "(OOOO):__setstate__",
+    if (!PyArg_ParseTuple(state, "OOOO",
                           &fn, &fnargs, &kw, &dict))
         return NULL;
     Py_XDECREF(pto->fn);
@@ -281,7 +281,7 @@
 
 static PyMethodDef partial_methods[] = {
     {"__reduce__", (PyCFunction)partial_reduce, METH_NOARGS},
-    {"__setstate__", (PyCFunction)partial_setstate, METH_VARARGS},
+    {"__setstate__", (PyCFunction)partial_setstate, METH_O},
     {NULL,              NULL}           /* sentinel */
 };
 
diff --git a/Modules/resource.c b/Modules/resource.c
index 1875e48..cadf9e6 100644
--- a/Modules/resource.c
+++ b/Modules/resource.c
@@ -144,10 +144,9 @@
 {
     struct rlimit rl;
     int resource;
-    PyObject *curobj, *maxobj;
+    PyObject *limits, *curobj, *maxobj;
 
-    if (!PyArg_ParseTuple(args, "i(OO):setrlimit",
-                          &resource, &curobj, &maxobj))
+    if (!PyArg_ParseTuple(args, "iO:setrlimit", &resource, &limits))
         return NULL;
 
     if (resource < 0 || resource >= RLIM_NLIMITS) {
@@ -156,21 +155,34 @@
         return NULL;
     }
 
+    limits = PySequence_Tuple(limits);
+    if (!limits)
+        /* Here limits is a borrowed reference */
+        return NULL;
+
+    if (PyTuple_GET_SIZE(limits) != 2) {
+        PyErr_SetString(PyExc_ValueError,
+                        "expected a tuple of 2 integers");
+        goto error;
+    }
+    curobj = PyTuple_GET_ITEM(limits, 0);
+    maxobj = PyTuple_GET_ITEM(limits, 1);
+
 #if !defined(HAVE_LARGEFILE_SUPPORT)
     rl.rlim_cur = PyLong_AsLong(curobj);
     if (rl.rlim_cur == (rlim_t)-1 && PyErr_Occurred())
-        return NULL;
+        goto error;
     rl.rlim_max = PyLong_AsLong(maxobj);
     if (rl.rlim_max == (rlim_t)-1 && PyErr_Occurred())
-        return NULL;
+        goto error;
 #else
     /* The limits are probably bigger than a long */
     rl.rlim_cur = PyLong_AsLongLong(curobj);
     if (rl.rlim_cur == (rlim_t)-1 && PyErr_Occurred())
-        return NULL;
+        goto error;
     rl.rlim_max = PyLong_AsLongLong(maxobj);
     if (rl.rlim_max == (rlim_t)-1 && PyErr_Occurred())
-        return NULL;
+        goto error;
 #endif
 
     rl.rlim_cur = rl.rlim_cur & RLIM_INFINITY;
@@ -184,10 +196,15 @@
                             "not allowed to raise maximum limit");
         else
             PyErr_SetFromErrno(ResourceError);
-        return NULL;
+        goto error;
     }
+    Py_DECREF(limits);
     Py_INCREF(Py_None);
     return Py_None;
+
+  error:
+    Py_DECREF(limits);
+    return NULL;
 }
 
 static PyObject *