Re: [PATCH] fs: fold open_check_o_direct into do_dentry_open

[Christoph Hellwig <hch@lst.de>]

On Thu, Apr 26, 2018 at 12:03:34AM +0900, J. R. Okajima wrote:
> Christoph Hellwig:
> > do_dentry_open is where we do the actual open of the file, so this is
> > where we should do our O_DIRECT sanity check to cover all potential
> > callers.
> 	:::
> > diff --git a/fs/namei.c b/fs/namei.c
> > index 920a828ab2ce..9d6d8e8aed55 100644
> > --- a/fs/namei.c
> > +++ b/fs/namei.c
> > @@ -3374,9 +3374,7 @@ static int do_last(struct nameidata *nd,
> >  		goto out;
> >  	*opened |= FILE_OPENED;
> >  opened:
> > -	error = open_check_o_direct(file);
> > -	if (!error)
> > -		error = ima_file_check(file, op->acc_mode, *opened);
> > +	error = ima_file_check(file, op->acc_mode, *opened);
> >  	if (!error && will_truncate)
> >  		error = handle_truncate(file);
> 
> Removing the check from here may cause a problem I am afraid.
> In open(O_ATOMIC|O_DIRECT) case, the check is totally gone, isn't it?

You mean O_DIRECT using ->atomic_open?

Those are supposed to call finish_open(), which calls do_dentry_open
and thus the O_DIRECT check.


>
> 
> 
> J. R. Okajima
---end quoted text---