f2fs: detect more inconsistent cases in sanity_check_node_footer()

Let's enhance sanity_check_node_footer() to detect more inconsistent
cases as below:

Node Type			Node Footer Info
===================		=============================
NODE_TYPE_REGULAR		inode = true and xnode = true
NODE_TYPE_INODE			inode = false or xnode = true
NODE_TYPE_XATTR			inode = true or xnode = false
NODE_TYPE_NON_INODE		inode = false

Signed-off-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

Author: chaseyu

fs/f2fs/node.c

@@ -1515,20 +1515,29 @@ int f2fs_sanity_check_node_footer(struct f2fs_sb_info *sbi,
 					struct folio *folio, pgoff_t nid,
 					enum node_type ntype, bool in_irq)
 {
+	bool is_inode, is_xnode;
+
 	if (unlikely(nid != nid_of_node(folio)))
 		goto out_err;
 
+	is_inode = IS_INODE(folio);
+	is_xnode = f2fs_has_xattr_block(ofs_of_node(folio));
+
 	switch (ntype) {
+	case NODE_TYPE_REGULAR:
+		if (is_inode && is_xnode)
+			goto out_err;
+		break;
 	case NODE_TYPE_INODE:
-		if (!IS_INODE(folio))
+		if (!is_inode || is_xnode)
 			goto out_err;
 		break;
 	case NODE_TYPE_XATTR:
-		if (!f2fs_has_xattr_block(ofs_of_node(folio)))
+		if (is_inode || !is_xnode)
 			goto out_err;
 		break;
 	case NODE_TYPE_NON_INODE:
-		if (IS_INODE(folio))
+		if (is_inode)
 			goto out_err;
 		break;
 	default: