diff --git a/src/_imaging.c b/src/_imaging.c
index a589ab8b68f..728adc07bd7 100644
--- a/src/_imaging.c
+++ b/src/_imaging.c
@@ -1285,6 +1285,10 @@ _histogram(ImagingObject *self, PyObject *args) {
 
     /* Build an integer list containing the histogram */
     list = PyList_New(h->bands * 256);
+    if (list == NULL) {
+        ImagingHistogramDelete(h);
+        return NULL;
+    }
     for (i = 0; i < h->bands * 256; i++) {
         PyObject *item;
         item = PyLong_FromLong(h->histogram[i]);
@@ -2190,6 +2194,10 @@ _getcolors(ImagingObject *self, PyObject *args) {
         Py_INCREF(out);
     } else {
         out = PyList_New(colors);
+        if (out == NULL) {
+            free(items);
+            return NULL;
+        }
         for (i = 0; i < colors; i++) {
             ImagingColorItem *v = &items[i];
             PyObject *item = Py_BuildValue(
@@ -4361,6 +4369,7 @@ PyInit__imaging(void) {
     m = PyModule_Create(&module_def);
 
     if (setup_module(m) < 0) {
+        Py_DECREF(m);
         return NULL;
     }
 
diff --git a/src/_imagingft.c b/src/_imagingft.c
index 4f44d6a7158..e0c28986570 100644
--- a/src/_imagingft.c
+++ b/src/_imagingft.c
@@ -1082,11 +1082,17 @@ font_getvarnames(FontObject *self) {
 
     num_namedstyles = master->num_namedstyles;
     list_names = PyList_New(num_namedstyles);
+    if (list_names == NULL) {
+        FT_Done_MM_Var(library, master);
+        return NULL;
+    }
 
     name_count = FT_Get_Sfnt_Name_Count(self->face);
     for (i = 0; i < name_count; i++) {
         error = FT_Get_Sfnt_Name(self->face, i, &name);
         if (error) {
+            Py_DECREF(list_names);
+            FT_Done_MM_Var(library, master);
             return geterror(error);
         }
 
@@ -1125,10 +1131,19 @@ font_getvaraxes(FontObject *self) {
     name_count = FT_Get_Sfnt_Name_Count(self->face);
 
     list_axes = PyList_New(num_axis);
+    if (list_axes == NULL) {
+        FT_Done_MM_Var(library, master);
+        return NULL;
+    }
     for (i = 0; i < num_axis; i++) {
         axis = master->axis[i];
 
         list_axis = PyDict_New();
+        if (list_axis == NULL) {
+            Py_DECREF(list_axes);
+            FT_Done_MM_Var(library, master);
+            return NULL;
+        }
         PyObject *minimum = PyLong_FromLong(axis.minimum / 65536);
         PyDict_SetItemString(list_axis, "minimum", minimum ? minimum : Py_None);
         Py_XDECREF(minimum);
@@ -1144,6 +1159,9 @@ font_getvaraxes(FontObject *self) {
         for (j = 0; j < name_count; j++) {
             error = FT_Get_Sfnt_Name(self->face, j, &name);
             if (error) {
+                Py_DECREF(list_axis);
+                Py_DECREF(list_axes);
+                FT_Done_MM_Var(library, master);
                 return geterror(error);
             }
 
diff --git a/src/_imagingmorph.c b/src/_imagingmorph.c
index 2e3545863c7..8815c2b7ec6 100644
--- a/src/_imagingmorph.c
+++ b/src/_imagingmorph.c
@@ -136,13 +136,18 @@ match(PyObject *self, PyObject *args) {
     int row_idx, col_idx;
     UINT8 **inrows;
     PyObject *ret = PyList_New(0);
+    if (ret == NULL) {
+        return NULL;
+    }
 
     if (!PyArg_ParseTuple(args, "On", &py_lut, &i0)) {
+        Py_DECREF(ret);
         PyErr_SetString(PyExc_RuntimeError, "Argument parsing problem");
         return NULL;
     }
 
     if (!PyBytes_Check(py_lut)) {
+        Py_DECREF(ret);
         PyErr_SetString(PyExc_RuntimeError, "The morphology LUT is not a bytes object");
         return NULL;
     }
@@ -150,6 +155,7 @@ match(PyObject *self, PyObject *args) {
     lut_len = PyBytes_Size(py_lut);
 
     if (lut_len < LUT_SIZE) {
+        Py_DECREF(ret);
         PyErr_SetString(PyExc_RuntimeError, "The morphology LUT has the wrong size");
         return NULL;
     }
@@ -158,6 +164,7 @@ match(PyObject *self, PyObject *args) {
     imgin = (Imaging)i0;
 
     if (imgin->type != IMAGING_TYPE_UINT8 || imgin->bands != 1) {
+        Py_DECREF(ret);
         PyErr_SetString(PyExc_RuntimeError, "Unsupported image type");
         return NULL;
     }
@@ -214,10 +221,13 @@ get_on_pixels(PyObject *self, PyObject *args) {
     int row_idx, col_idx;
     int width, height;
     PyObject *ret = PyList_New(0);
+    if (ret == NULL) {
+        return NULL;
+    }
 
     if (!PyArg_ParseTuple(args, "n", &i0)) {
+        Py_DECREF(ret);
         PyErr_SetString(PyExc_RuntimeError, "Argument parsing problem");
-
         return NULL;
     }
     img = (Imaging)i0;
diff --git a/src/_imagingtk.c b/src/_imagingtk.c
index b9273b0b882..efa7fc1b6fa 100644
--- a/src/_imagingtk.c
+++ b/src/_imagingtk.c
@@ -58,5 +58,9 @@ PyInit__imagingtk(void) {
     };
     PyObject *m;
     m = PyModule_Create(&module_def);
-    return (load_tkinter_funcs() == 0) ? m : NULL;
+    if (load_tkinter_funcs() != 0) {
+        Py_DECREF(m);
+        return NULL;
+    }
+    return m;
 }
diff --git a/src/_webp.c b/src/_webp.c
index 1667bd17488..fe63027fbd9 100644
--- a/src/_webp.c
+++ b/src/_webp.c
@@ -990,6 +990,7 @@ PyInit__webp(void) {
 
     m = PyModule_Create(&module_def);
     if (setup_module(m) < 0) {
+        Py_DECREF(m);
         return NULL;
     }
 
diff --git a/src/path.c b/src/path.c
index 3e3431575ec..e17580fa227 100644
--- a/src/path.c
+++ b/src/path.c
@@ -439,6 +439,9 @@ path_tolist(PyPathObject *self, PyObject *args) {
 
     if (flat) {
         list = PyList_New(self->count * 2);
+        if (list == NULL) {
+            return NULL;
+        }
         for (i = 0; i < self->count * 2; i++) {
             PyObject *item;
             item = PyFloat_FromDouble(self->xy[i]);
@@ -449,6 +452,9 @@ path_tolist(PyPathObject *self, PyObject *args) {
         }
     } else {
         list = PyList_New(self->count);
+        if (list == NULL) {
+            return NULL;
+        }
         for (i = 0; i < self->count; i++) {
             PyObject *item;
             item = Py_BuildValue("dd", self->xy[i + i], self->xy[i + i + 1]);