ext2_rename(): set_link and delete_entry may fail

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Tested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>

Author: Al Viro

fs/ext2/dir.c

@@ -606,8 +606,7 @@ int ext2_delete_entry (struct ext2_dir_entry_2 *dir, struct page *page,
 		if (de->rec_len == 0) {
 			ext2_error(inode->i_sb, __func__,
 				"zero-length directory entry");
-			err = -EIO;
-			goto out;
+			return -EIO;
 		}
 		pde = de;
 		de = ext2_next_entry(de);
@@ -617,17 +616,18 @@ int ext2_delete_entry (struct ext2_dir_entry_2 *dir, struct page *page,
 	pos = page_offset(page) + from;
 	lock_page(page);
 	err = ext2_prepare_chunk(page, pos, to - from);
-	BUG_ON(err);
+	if (err) {
+		unlock_page(page);
+		return err;
+	}
 	if (pde)
 		pde->rec_len = ext2_rec_len_to_disk(to - from);
 	dir->inode = 0;
 	ext2_commit_chunk(page, pos, to - from);
 	inode->i_ctime = inode->i_mtime = current_time(inode);
 	EXT2_I(inode)->i_flags &= ~EXT2_BTREE_FL;
 	mark_inode_dirty(inode);
-	err = ext2_handle_dirsync(inode);
-out:
-	return err;
+	return ext2_handle_dirsync(inode);
 }
 
 /*

fs/ext2/namei.c

@@ -335,18 +335,16 @@ static int ext2_rename (struct mnt_idmap * idmap,
 
 	err = dquot_initialize(old_dir);
 	if (err)
-		goto out;
+		return err;
 
 	err = dquot_initialize(new_dir);
 	if (err)
-		goto out;
+		return err;
 
 	old_de = ext2_find_entry(old_dir, &old_dentry->d_name, &old_page,
 				 &old_page_addr);
-	if (IS_ERR(old_de)) {
-		err = PTR_ERR(old_de);
-		goto out;
-	}
+	if (IS_ERR(old_de))
+		return PTR_ERR(old_de);
 
 	if (S_ISDIR(old_inode->i_mode)) {
 		err = -EIO;
@@ -394,27 +392,20 @@ static int ext2_rename (struct mnt_idmap * idmap,
 	old_inode->i_ctime = current_time(old_inode);
 	mark_inode_dirty(old_inode);
 
-	ext2_delete_entry(old_de, old_page, old_page_addr);
-
-	if (dir_de) {
-		if (old_dir != new_dir) {
+	err = ext2_delete_entry(old_de, old_page, old_page_addr);
+	if (!err && dir_de) {
+		if (old_dir != new_dir)
 			err = ext2_set_link(old_inode, dir_de, dir_page,
 					    dir_page_addr, new_dir, false);
 
-		}
-		ext2_put_page(dir_page, dir_page_addr);
 		inode_dec_link_count(old_dir);
 	}
-
-out_old:
-	ext2_put_page(old_page, old_page_addr);
-out:
-	return err;
-
 out_dir:
 	if (dir_de)
 		ext2_put_page(dir_page, dir_page_addr);
-	goto out_old;
+out_old:
+	ext2_put_page(old_page, old_page_addr);
+	return err;
 }
 
 const struct inode_operations ext2_dir_inode_operations = {