sysv: i_nlink races in rename()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/sysv/namei.c

@@ -245,7 +245,6 @@ static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
 		new_de = sysv_find_entry(new_dentry, &new_page);
 		if (!new_de)
 			goto out_dir;
-		inode_inc_link_count(old_inode);
 		sysv_set_link(new_de, new_page, old_inode);
 		new_inode->i_ctime = CURRENT_TIME_SEC;
 		if (dir_de)
@@ -257,18 +256,15 @@ static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
 			if (new_dir->i_nlink >= SYSV_SB(new_dir->i_sb)->s_link_max)
 				goto out_dir;
 		}
-		inode_inc_link_count(old_inode);
 		err = sysv_add_link(new_dentry, old_inode);
-		if (err) {
-			inode_dec_link_count(old_inode);
+		if (err)
 			goto out_dir;
-		}
 		if (dir_de)
 			inode_inc_link_count(new_dir);
 	}
 
 	sysv_delete_entry(old_de, old_page);
-	inode_dec_link_count(old_inode);
+	mark_inode_dirty(old_inode);
 
 	if (dir_de) {
 		sysv_set_link(dir_de, dir_page, new_dir);