Re: [PATCH v7 0/7] Add O_DENY* support for VFS and CIFS/NFS

From: Volker Lendecke
Date: Mon Jan 20 2014 - 05:31:39 EST


On Mon, Jan 20, 2014 at 02:20:43PM +0400, Pavel Shilovsky wrote:
> > One question: If Samba wants to open a file for delete
> > access, there's no corresponding flag in the open
> > permissions. There can be the case where Samba wants to open
> > *just* for future unlink, no read or write access required.
> > Is there a way to achieve this atomically correct?
>
> You can try to use O_PATH flag. It doesn't give you a delete access
> but should be ok because further deleting will be done without file
> descriptor -- through unlink syscall.

Ok, I did not know about O_PATH. Thanks for that!

So I do an open with O_PATH. How do I then make sure that
nobody else has a O_DENYDELETE set without doing the unlink
itself?

Thanks,

Volker

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