4.19-stable review patch. If anyone has any objections, please let me know.
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From: Boris Burkov boris@bur.io
commit 0c309d66dacddf8ce939b891d9ead4a8e21ad6f0 upstream.
Creating a qgroup 0/subvolid leads to various races and it isn't helpful, because you can't specify a subvol id when creating a subvol, so you can't be sure it will be the right one. Any requirements on the automatic subvol can be gratified by using a higher level qgroup and the inheritance parameters of subvol creation.
Fixes: cecbb533b5fc ("btrfs: record simple quota deltas in delayed refs") CC: stable@vger.kernel.org # 4.14+ Reviewed-by: Qu Wenruo wqu@suse.com Signed-off-by: Boris Burkov boris@bur.io Reviewed-by: David Sterba dsterba@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/ioctl.c | 5 +++++ 1 file changed, 5 insertions(+)
--- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -5343,6 +5343,11 @@ static long btrfs_ioctl_qgroup_create(st goto out; }
+ if (sa->create && is_fstree(sa->qgroupid)) { + ret = -EINVAL; + goto out; + } + trans = btrfs_join_transaction(root); if (IS_ERR(trans)) { ret = PTR_ERR(trans);