[PATCH 15/43] btrfs: hold a ref on the root in create_subvol

Josef Bacik
2020-01-17T21:26:36Z

We're creating the new root here, but we should hold the ref until after
we've initialized the inode for it.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
---
fs/btrfs/ioctl.c | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 958c0245c363..b1d74cb09cb4 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -672,10 +672,16 @@ static noinline int create_subvol(struct inode *dir,
btrfs_abort_transaction(trans, ret);
goto fail;
}
+ if (!btrfs_grab_fs_root(new_root)) {
+ ret = -ENOENT;
+ btrfs_abort_transaction(trans, ret);
+ goto fail;
+ }

btrfs_record_root_in_trans(trans, new_root);

ret = btrfs_create_subvol_root(trans, new_root, root, new_dirid);
+ btrfs_put_fs_root(new_root);
if (ret) {
/* We potentially lose an unused inode item here */
btrfs_abort_transaction(trans, ret);
--
2.24.1