Re: [PATCH v2 3/6] btrfs: qgroup: fix leak of qgroups in rb tree after failure to enable quotas

[Qu Wenruo <wqu@suse.com>]

在 2026/10/4 03:30, fdmanana@kernel.org 写道:
> From: Filipe Manana <fdmanana@suse.com>
> 
> When enabling quotas we add struct btrfs_qroup items to the rbtree
> fs_info->qgroup_tree, however if there's an error during the quota enable
> operation after adding those items, we exit without removing the items
> from the rbtree and freeing them.
> 
> Fix this by calling btrfs_free_qgroup_config() on error, which also
> deletes all sysfs entries (it calls btrfs_sysfs_del_qgroups()).
> 
> Signed-off-by: Filipe Manana <fdmanana@suse.com>

Reviewed-by: Qu Wenruo <wqu@suse.com>

Thanks,
Qu> ---
>   fs/btrfs/qgroup.c | 9 +++++++--
>   1 file changed, 7 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
> index 4b6c82a24bc5..9f21b091c545 100644
> --- a/fs/btrfs/qgroup.c
> +++ b/fs/btrfs/qgroup.c
> @@ -1293,8 +1293,13 @@ int btrfs_quota_enable(struct btrfs_fs_info *fs_info,
>   	if (ret)
>   		btrfs_put_root(quota_root);
>   out:
> -	if (ret)
> -		btrfs_sysfs_del_qgroups(fs_info);
> +	if (ret) {
> +		/*
> +		 * Free all qgroups previously added with add_qgroup_rb() and
> +		 * sysfs entries.
> +		 */
> +		btrfs_free_qgroup_config(fs_info);
> +	}
>   	mutex_unlock(&fs_info->qgroup_ioctl_lock);
>   	if (ret && trans)
>   		btrfs_end_transaction(trans);