When we create a qgroup inheriting a qgroup, we need to check the level of them. Otherwise, there is a chance where a qgroup can inherit another qgroup at the same level.
Signed-off-by: Dongsheng Yang <[email protected]> --- fs/btrfs/qgroup.c | 6 ++++++ fs/btrfs/qgroup.h | 9 +++++++++ 2 files changed, 15 insertions(+) diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c index 953befd..c2983a4 100644 --- a/fs/btrfs/qgroup.c +++ b/fs/btrfs/qgroup.c @@ -2221,6 +2221,12 @@ int btrfs_qgroup_inherit(struct btrfs_trans_handle *trans, ret = -EINVAL; goto out; } + + if ((srcgroup->qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT) <= + (objectid >> BTRFS_QGROUP_LEVEL_SHIFT)) { + ret = -EINVAL; + goto out; + } ++i_qgroups; } } diff --git a/fs/btrfs/qgroup.h b/fs/btrfs/qgroup.h index 18cc68c..67291ff 100644 --- a/fs/btrfs/qgroup.h +++ b/fs/btrfs/qgroup.h @@ -20,6 +20,15 @@ #define __BTRFS_QGROUP__ /* + * The ID of a qgroup consists of a level and a id, looks like: 1/3. + * The 1 is the level means this qgroup is in the level 1 and the 3 + * is the id of this qgroup in level 1. We use a u64 number store a + * qgroup ID, the first 16bits stands for the level and the last 48bits + * stands for the id. + */ +#define BTRFS_QGROUP_LEVEL_SHIFT 48 + +/* * A description of the operations, all of these operations only happen when we * are adding the 1st reference for that subvolume in the case of adding space * or on the last reference delete in the case of subtraction. The only -- 1.8.4.2 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
