From 3bcc064fe9fef7748b371c95e2cdddfe6e30e305 Mon Sep 17 00:00:00 2001 From: Hans van Kranenburg Date: Fri, 1 Mar 2019 20:04:53 +0100 Subject: [PATCH] ctree: Fix crash because of stray underscores The tree_block_refs and shared_block_refs attributes of the MetaDataItem class are of type list. This means they have an append function, and not _append. So hitting these lines of code crash a program with "AttributeError: 'list' object has no attribute '_append'" This made me find out that both of the filesystems that I use for regression testing before doing a release were originally created using Debian Jessie, and they were never converted to enable the skinny_metadata feature, which introduces the usage of these MetaDataItem objects. Unfortunately this means that working with metadata related information from the extent tree is pretty much broken for any recently created filesystem. Also affected is the btrfs-heatmap program, which will crash while generating pictures on extent level of metadata block groups. Andrei Borzenkov reported this bug, and found it by using the show_metadata_tree_sizes example. Fixes: 899fdf4c52 "ctree: hide internal ref item helpers" Closes: https://github.com/knorrie/python-btrfs/issues/17 --- btrfs/ctree.py | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/btrfs/ctree.py b/btrfs/ctree.py index 30c04e8..6aef8d7 100644 --- a/btrfs/ctree.py +++ b/btrfs/ctree.py @@ -1438,9 +1438,9 @@ class MetaDataItem(ItemData): inline_ref_type, inline_ref_offset = \ ExtentItem._extent_inline_ref.unpack_from(data, pos) if inline_ref_type == TREE_BLOCK_REF_KEY: - self.tree_block_refs._append(InlineTreeBlockRef(inline_ref_offset)) + self.tree_block_refs.append(InlineTreeBlockRef(inline_ref_offset)) elif inline_ref_type == SHARED_BLOCK_REF_KEY: - self.shared_block_refs._append(InlineSharedBlockRef(inline_ref_offset)) + self.shared_block_refs.append(InlineSharedBlockRef(inline_ref_offset)) else: raise Exception("BUG: expected inline TREE_BLOCK_REF or SHARED_BLOCK_REF_KEY " "in METADATA_ITEM {}, but got inline_ref_type {}" -- 2.20.1