Re: [PATCH 0/5] Enhancement for block group/chunk verification

[David Sterba <dsterba@suse.cz>]

On Tue, Jul 03, 2018 at 05:10:04PM +0800, Qu Wenruo wrote:
> Can be fetched from github, which is based on v4.18-rc1 tag:
> https://github.com/adam900710/linux/tree/tree_checker_enhance
> 
> Reported by Xu Wen <wen.xu@gatech.edu>, some crafted btrfs image can
> cause unexpected kernel behavior.
> 
> All of them are related to block group and chunk, so this patchset will
> enhance block group and chunk verification, so kernel can detect them
> and error out gracefully (with user friendly error message showing
> what's going wrong)
> 
> Obvious corruption (don't need to cross check with chunk/block group),
> will be addressed by enhanced tree-checker.
> (Most crafted images will be caught by tree-checker)
> 
> More complex corruption will be addressed mostly at
> btrfs_read_block_groups(), doing extra cross reference check for
> chunk<->block group mapping.
> It may cause extra mount time, but compared to the existing time
> consuming block group items search, all added check is done completely
> in memory using rb_tree, so it shouldn't add too much overhead.
> 
> Qu Wenruo (5):
>   btrfs: tree-checker: Verify block_group_item
>   btrfs: tree-checker: Detect invalid empty essential tree
>   btrfs: relocation: Only remove reloc rb_trees if reloc control has
>     been initialized
>   btrfs: Check each block group has corresponding chunk at mount time
>   btrfs: Verify every chunk has corresponding block group at mount time

Patches 1-3 queued, thanks. 4 and 5 have some comments.