Re: [PATCH] ocfs2: fix orphan inode disk leak in ocfs2_dio_end_io() on I/O error

Heming Zhao <[email protected]> Mon, 15 Jun 2026 23:09:31 +0800
Newsgroups dev.linux.lists.ocfs2-devel,org.kernel.vger.linux-kernel
Message-ID <ajAP6648UpilAPXz@p15>
On Fri, Jun 12, 2026 at 02:58:41PM +0200, Marco Elver wrote:
> On Fri, Jun 12, 2026 at 09:27AM +0800, Heming Zhao wrote:
> > On Thu, Jun 11, 2026 at 05:01:50PM +0200, Marco Elver wrote:
> > > When an extending direct I/O write or a direct I/O write racing with an
> > > unlink is initiated, ocfs2_direct_IO() places the user inode into the
> > > system orphan directory and sets the OCFS2_DIO_ORPHANED_FL flag to
> > > ensure defined behavior and crash consistency.
> > > 
> > > However, if the direct I/O request encounters an error or gets
> > > asynchronous cancellation (bytes <= 0), the VFS completion hook
> > > ocfs2_dio_end_io() bypasses ocfs2_dio_end_io_write() entirely and
> > > executes ocfs2_dio_free_write_ctx().  This completely omits the teardown
> > > of the orphan entry, leaking the user inode in the orphan directory and
> > > leaving the OCFS2_DIO_ORPHANED_FL disk flag set.
> > > 
> > > Because the OCFS2_DIO_ORPHANED_FL flag remains active, subsequent VFS
> > > final inode eviction (ocfs2_delete_inode) observes the flag, assumes a
> > > direct I/O write is actively in progress, and refuses to wipe the inode.
> > > This results in an irrecoverable disk storage and resource leak that can
> > > only be reclaimed if the cluster unmounts or crashes.
> > > 
> > > Fix this by ensuring that ocfs2_dio_end_io() inspects dw_orphaned even
> > > when an I/O error occurs, and executes ocfs2_del_inode_from_orphan() to
> > > liberate the inode before destroying the in-memory write context.
> > > 
> > > Fixes: 5040f8df56fb ("ocfs2: free up write context when direct IO failed")
> > > Assisted-by: Antigravity:Gemini
> > > Signed-off-by: Marco Elver <[email protected]>
> > > ---
> > >  fs/ocfs2/aops.c | 17 +++++++++++++++--
> > >  1 file changed, 15 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
> > > index 4acdbb70882c..ad3f2057e26e 100644
> > > --- a/fs/ocfs2/aops.c
> > > +++ b/fs/ocfs2/aops.c
> > > @@ -2419,11 +2419,24 @@ static int ocfs2_dio_end_io(struct kiocb *iocb,
> > >  		mlog_ratelimited(ML_ERROR, "Direct IO failed, bytes = %lld",
> > >  				 (long long)bytes);
> > >  	if (private) {
> > > -		if (bytes > 0)
> > > +		if (bytes > 0) {
> > >  			ret = ocfs2_dio_end_io_write(inode, private, offset,
> > >  						     bytes);
> > > -		else
> > > +		} else {
> > > +			struct ocfs2_dio_write_ctxt *dwc = private;
> > > +
> > > +			if (dwc->dw_orphaned) {
> > > +				struct buffer_head *di_bh = NULL;
> > > +
> > > +				if (ocfs2_inode_lock(inode, &di_bh, 1) == 0) {
> > > +					ocfs2_del_inode_from_orphan(OCFS2_SB(inode->i_sb),
> > > +								    inode, di_bh, 0, 0);
> > > +					ocfs2_inode_unlock(inode, 1);
> > > +					brelse(di_bh);
> > > +				}
> > 
> > Calling only ocfs2_del_inode_from_orphan() without ocfs2_truncate_file() will
> > leave stale blocks beyond the EOF.
> 
> Right.
> 
> > I think the existing OCFS2 code already handles error/crash cases for orphaned
> > inodes, and this "leaking" behavior is by design.
> > please refer to ocfs2_recover_orphans() and ocfs2_add_inode_to_orphan().
> 
> Periodic scans skip direct I/O entries to avoid racing with active
> direct I/O on live nodes:
> 
> In fs/ocfs2/journal.c:ocfs2_orphan_filldir():
> 
> 	/* do not include dio entry in case of orphan scan */
> 	if ((p->orphan_reco_type == ORPHAN_NO_NEED_TRUNCATE) &&
> 			(!strncmp(name, OCFS2_DIO_ORPHAN_PREFIX,
> 			OCFS2_DIO_ORPHAN_PREFIX_LEN)))
> 		return true;
> 
> Is something else recovering them?

Searching for ORPHAN_NEED_TRUNCATE, i.e.:
- ocfs2_recover_node() calls ocfs2_queue_recovery_completion() with the
  ORPHAN_NEED_TRUNCATE flag.
- ocfs2_complete_mount_recovery() calls subroutines with the
  ORPHAN_NEED_TRUNCATE flag.

ocfs2 is a cluster fs. When one node crashes, another node handles the recovery.

- Heming