Re: [PATCH v2 1/7] xfs: rework refcount cow recovery error handling

["Darrick J. Wong" <darrick.wong@oracle.com>]

On Mon, Oct 10, 2016 at 03:21:13AM -0700, Christoph Hellwig wrote:
> On Sun, Oct 09, 2016 at 11:11:22PM -0700, Darrick J. Wong wrote:
> > The error handling in xfs_refcount_recover_cow_leftovers is confused
> > and can potentially leak memory, so rework it to release resources
> > correctly on error.
> > 
> > Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> > Reported-by: Brian Foster <bfoster@redhat.com>
> > ---
> >  fs/xfs/libxfs/xfs_refcount.c |   16 ++++++----------
> >  1 file changed, 6 insertions(+), 10 deletions(-)
> > 
> > diff --git a/fs/xfs/libxfs/xfs_refcount.c b/fs/xfs/libxfs/xfs_refcount.c
> > index 56bfef1..955b1d9 100644
> > --- a/fs/xfs/libxfs/xfs_refcount.c
> > +++ b/fs/xfs/libxfs/xfs_refcount.c
> > @@ -1643,7 +1643,7 @@ xfs_refcount_recover_cow_leftovers(
> >  	error = xfs_btree_query_range(cur, &low, &high,
> >  			xfs_refcount_recover_extent, &debris);
> >  	if (error)
> > -		goto out_error;
> > +		goto out_cursor;
> >  	xfs_btree_del_cursor(cur, XFS_BTREE_NOERROR);
> >  	xfs_buf_relse(agbp);
> >  
> > @@ -1675,26 +1675,22 @@ xfs_refcount_recover_cow_leftovers(
> >  
> >  		error = xfs_trans_commit(tp);
> >  		if (error)
> > +			goto out_free;
> >  	}
> >  	goto out_free;
> 
> don't we need to also delete the cursor after a successful exit?

Gah.  Yeah.  Serves me right for trying to code patches on Sunday night.

I think Dave already made a separate fix, though, so I'll wait for the
next for-next update and see what needs to be fixed.

--D