Re: [PATCH] btrfs: fix transaction handle leak after verity rollback failure

[Boris Burkov <boris@bur.io>]

On Wed, Sep 08, 2021 at 04:29:26PM +0100, fdmanana@kernel.org wrote:
> From: Filipe Manana <fdmanana@suse.com>
> 
> During a verity rollback, if we fail to update the inode or delete the
> orphan, we abort the transaction and return without releasing our
> transaction handle. Fix that by releasing the handle.
> 
> Fixes: 146054090b0859 ("btrfs: initial fsverity support")
> Fixes: 705242538ff348 ("btrfs: verity metadata orphan items")
> Signed-off-by: Filipe Manana <fdmanana@suse.com>
Oops, I thoughtlessly assumed abort also released the handle. Thank you
for the fix!
Reviewed-by: Boris Burkov <boris@bur.io>
> ---
>  fs/btrfs/verity.c | 6 ++++--
>  1 file changed, 4 insertions(+), 2 deletions(-)
> 
> diff --git a/fs/btrfs/verity.c b/fs/btrfs/verity.c
> index 28d443d3ef93..4968535dfff0 100644
> --- a/fs/btrfs/verity.c
> +++ b/fs/btrfs/verity.c
> @@ -451,7 +451,7 @@ static int del_orphan(struct btrfs_trans_handle *trans, struct btrfs_inode *inod
>   */
>  static int rollback_verity(struct btrfs_inode *inode)
>  {
> -	struct btrfs_trans_handle *trans;
> +	struct btrfs_trans_handle *trans = NULL;
>  	struct btrfs_root *root = inode->root;
>  	int ret;
>  
> @@ -473,6 +473,7 @@ static int rollback_verity(struct btrfs_inode *inode)
>  	trans = btrfs_start_transaction(root, 2);
>  	if (IS_ERR(trans)) {
>  		ret = PTR_ERR(trans);
> +		trans = NULL;
>  		btrfs_handle_fs_error(root->fs_info, ret,
>  			"failed to start transaction in verity rollback %llu",
>  			(u64)inode->vfs_inode.i_ino);
> @@ -490,8 +491,9 @@ static int rollback_verity(struct btrfs_inode *inode)
>  		btrfs_abort_transaction(trans, ret);
>  		goto out;
>  	}
> -	btrfs_end_transaction(trans);
>  out:
> +	if (trans)
> +		btrfs_end_transaction(trans);
>  	return ret;
>  }
>  
> -- 
> 2.33.0
>