Pillow: Heap out-of-bounds write in `ImageFilter.RankFilter` via integer overflow in `ImagingExpand`

Summary Pillow's public rank-filter API can trigger a native heap out-of-bounds write when given a very large odd filter size. Minimal public API trigger: python from PIL import Image, ImageFilter im = Image.new"L", 3, 3, 128 im.filterImageFilter.MedianFilter4294967295 ImageFilter.RankFilter.filt...