Raise an error if co-ordinates are incorrectly ordered

Tests/test_imagedraw.py

@@ -355,7 +355,13 @@ def ellipse_various_sizes_helper(filled):
     for w in ellipse_sizes:
         y = 1
         for h in ellipse_sizes:
-            border = [x, y, x + w - 1, y + h - 1]
+            x1 = x + w
+            if w:
+                x1 -= 1
+            y1 = y + h
+            if h:
+                y1 -= 1
+            border = [x, y, x1, y1]
             if filled:
                 draw.ellipse(border, fill="white")
             else:
@@ -932,9 +938,6 @@ def test_square():
     img, draw = create_base_image_draw((10, 10))
     draw.rectangle((2, 2, 7, 7), BLACK)
     assert_image_equal_tofile(img, expected, "square as normal rectangle failed")
-    img, draw = create_base_image_draw((10, 10))
-    draw.rectangle((7, 7, 2, 2), BLACK)
-    assert_image_equal_tofile(img, expected, "square as inverted rectangle failed")
 
 
 def test_triangle_right():
@@ -1499,3 +1502,20 @@ def test_polygon2():
     draw.polygon([(18, 30), (19, 31), (18, 30), (85, 30), (60, 72)], "red")
     expected = "Tests/images/imagedraw_outline_polygon_RGB.png"
     assert_image_similar_tofile(im, expected, 1)
+
+
+def test_incorrectly_ordered_coordinates():
+    im = Image.new("RGB", (W, H))
+    draw = ImageDraw.Draw(im)
+    with pytest.raises(TypeError):
+        draw.arc((1, 1, 0, 0), 10, 260)
+    with pytest.raises(TypeError):
+        draw.chord((1, 1, 0, 0), 10, 260)
+    with pytest.raises(TypeError):
+        draw.ellipse((1, 1, 0, 0))
+    with pytest.raises(TypeError):
+        draw.pieslice((1, 1, 0, 0), 10, 260)
+    with pytest.raises(TypeError):
+        draw.rectangle((1, 1, 0, 0))
+    with pytest.raises(TypeError):
+        draw.rounded_rectangle((1, 1, 0, 0))

src/PIL/ImageDraw.py

@@ -303,6 +303,12 @@ def rounded_rectangle(
             (x0, y0), (x1, y1) = xy
         else:
             x0, y0, x1, y1 = xy
+        if x1 < x0 or y1 < y0:
+            msg = (
+                "x1 must be greater than or equal to x0,"
+                " and y1 must be greater than or equal to y0"
+            )
+            raise TypeError(msg)
         if corners is None:
             corners = (True, True, True, True)
 

src/_imaging.c

@@ -251,6 +251,8 @@ PyImaging_GetBuffer(PyObject *buffer, Py_buffer *view) {
 static const char *must_be_sequence = "argument must be a sequence";
 static const char *must_be_two_coordinates =
     "coordinate list must contain exactly 2 coordinates";
+static const char *incorrectly_ordered_coordinates =
+    "x1 must be greater than or equal to x0, and y1 must be greater than or equal to y0";
 static const char *wrong_mode = "unrecognized image mode";
 static const char *wrong_raw_mode = "unrecognized raw mode";
 static const char *outside_image = "image index out of range";
@@ -2805,6 +2807,11 @@ _draw_arc(ImagingDrawObject *self, PyObject *args) {
         free(xy);
         return NULL;
     }
+    if (xy[2] < xy[0] || xy[3] < xy[1]) {
+        PyErr_SetString(PyExc_TypeError, incorrectly_ordered_coordinates);
+        free(xy);
+        return NULL;
+    }
 
     n = ImagingDrawArc(
         self->image->image,
@@ -2886,6 +2893,11 @@ _draw_chord(ImagingDrawObject *self, PyObject *args) {
         free(xy);
         return NULL;
     }
+    if (xy[2] < xy[0] || xy[3] < xy[1]) {
+        PyErr_SetString(PyExc_TypeError, incorrectly_ordered_coordinates);
+        free(xy);
+        return NULL;
+    }
 
     n = ImagingDrawChord(
         self->image->image,
@@ -2932,6 +2944,11 @@ _draw_ellipse(ImagingDrawObject *self, PyObject *args) {
         free(xy);
         return NULL;
     }
+    if (xy[2] < xy[0] || xy[3] < xy[1]) {
+        PyErr_SetString(PyExc_TypeError, incorrectly_ordered_coordinates);
+        free(xy);
+        return NULL;
+    }
 
     n = ImagingDrawEllipse(
         self->image->image,
@@ -3101,6 +3118,11 @@ _draw_pieslice(ImagingDrawObject *self, PyObject *args) {
         free(xy);
         return NULL;
     }
+    if (xy[2] < xy[0] || xy[3] < xy[1]) {
+        PyErr_SetString(PyExc_TypeError, incorrectly_ordered_coordinates);
+        free(xy);
+        return NULL;
+    }
 
     n = ImagingDrawPieslice(
         self->image->image,
@@ -3197,6 +3219,11 @@ _draw_rectangle(ImagingDrawObject *self, PyObject *args) {
         free(xy);
         return NULL;
     }
+    if (xy[2] < xy[0] || xy[3] < xy[1]) {
+        PyErr_SetString(PyExc_TypeError, incorrectly_ordered_coordinates);
+        free(xy);
+        return NULL;
+    }
 
     n = ImagingDrawRectangle(
         self->image->image,