iomap: Add another assertion to inline data handling

Check that the file tail does not cross a page boundary.  Requested by
Andreas.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

fs/iomap/buffered-io.c

@@ -215,6 +215,8 @@ static int iomap_read_inline_data(struct inode *inode, struct page *page,
 	if (PageUptodate(page))
 		return PAGE_SIZE - poff;
 
+	if (WARN_ON_ONCE(size > PAGE_SIZE - poff))
+		return -EIO;
 	if (WARN_ON_ONCE(size > PAGE_SIZE -
 			 offset_in_page(iomap->inline_data)))
 		return -EIO;