Re: [PATCH v4] ceph: mark directory as non-complete complete after loading key

[Gregory Farnum]

On Tue, Nov 29, 2022 at 7:21 AM Ilya Dryomov <idryomov@xxxxxxxxx> wrote:
>
> On Tue, Nov 29, 2022 at 3:50 PM Xiubo Li <xiubli@xxxxxxxxxx> wrote:
> >
> >
> > On 29/11/2022 22:32, Ilya Dryomov wrote:
> > > On Tue, Nov 29, 2022 at 3:15 PM Xiubo Li <xiubli@xxxxxxxxxx> wrote:
> > >>
> > >> On 29/11/2022 18:39, Luís Henriques wrote:
> > >>> When setting a directory's crypt context, ceph_dir_clear_complete() needs to
> > >>> be called otherwise if it was complete before, any existing (old) dentry will
> > >>> still be valid.
> > >>>
> > >>> This patch adds a wrapper around __fscrypt_prepare_readdir() which will
> > >>> ensure a directory is marked as non-complete if key status changes.
> > >>>
> > >>> Signed-off-by: Luís Henriques <lhenriques@xxxxxxx>
> > >>> ---
> > >>> Hi Xiubo,
> > >>>
> > >>> Here's a rebase of this patch.  I did some testing but since this branch
> > >>> doesn't really have full fscrypt support, I couldn't even reproduce the
> > >>> bug.  So, my testing was limited.
> > >> I'm planing not to update the wip-fscrypt branch any more, except the IO
> > >> path related fixes, which may introduce potential bugs each time as before.
> > >>
> > >> Since the qa tests PR has finished and the tests have passed, so we are
> > >> planing to merge the first none IO part, around 27 patches. And then
> > >> pull the reset patches from wip-fscrypt branch.
> > > I'm not sure if merging metadata and I/O path patches separately
> > > makes sense.  What would a user do with just filename encryption?
> >
> > Hi Ilya,
> >
> > I think the IO ones should be followed soon.
> >
> > Currently the filename ones have been well testes. And the contents will
> > be by passed for now.
> >
> > Since this is just for Dev Preview feature IMO it should be okay (?)
>
> I don't think there is such a thing as a Dev Preview feature when it
> comes to the mainline kernel, particularly in the area of filesystems
> and storage.  It should be ready for users at least to some extent.  So
> my question stands: what would a user do with just filename encryption?

I think how this merges is up to you guys and the kernel practices.
Merging only the filename encryption is definitely of *limited*
utility, but I don't think it's totally pointless -- the data versus
metadata paths are different and you are protecting against somewhat
different vulnerabilities and threat models with them. For instance,
MDS logs dump filenames, but OSD logs do not dump object data. There's
some obvious utility there even if you basically trust your provider,
or run your own cluster but want to be more secure about sending logs
via ceph-post-file.
-Greg

>
> Thanks,
>
>                 Ilya
>