btrfs: Check qgroup level in kernel qgroup assign.
Although we have qgroup level check in btrfs-progs, it's not enough
since other programe may still call ioctl directly not using
btrfs-progs. For example, systemd.
But it's btrfs-progs to be blame since we don't provide a
full-function(like subvolume create things) btrfs library with enough
check, and only rely on kernel ioctl.
So Add level checks in kernel too.
Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Reviewed-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: Chris Mason <clm@fb.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 851f235..8b851ac 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1061,6 +1061,12 @@
__le64 flags;
} __attribute__ ((__packed__));
+#define BTRFS_QGROUP_LEVEL_SHIFT 48
+static inline u64 btrfs_qgroup_level(u64 qgroupid)
+{
+ return qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT;
+}
+
/*
* is subvolume quota turned on?
*/
diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 464d1e2..4fb9610 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1009,6 +1009,10 @@
struct btrfs_qgroup_list *list;
int ret = 0;
+ /* Check the level of src and dst first */
+ if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
+ return -EINVAL;
+
mutex_lock(&fs_info->qgroup_ioctl_lock);
quota_root = fs_info->quota_root;
if (!quota_root) {