On Mon, May 18, 2020 at 8:47 PM Luis Henriques <lhenriques@xxxxxxxx> wrote:
>
> Similarly to commit 03f219041fdb ("ceph: check i_nlink while converting
> a file handle to dentry"), this fixes another corner case with
> name_to_handle_at/open_by_handle_at. The issue has been detected by
> xfstest generic/467, when doing:
>
> - name_to_handle_at("/cephfs/myfile")
> - open("/cephfs/myfile")
> - unlink("/cephfs/myfile")
> - sync; sync;
> - drop caches
> - open_by_handle_at()
>
> The call to open_by_handle_at should not fail because the file hasn't been
> deleted yet (only unlinked) and we do have a valid handle to it. -ESTALE
> shall be returned only if i_nlink is 0 *and* i_count is 1.
>
> This patch also makes sure we have LINK caps before checking i_nlink.
>
> Signed-off-by: Luis Henriques <lhenriques@xxxxxxxx>
> ---
> Hi!
>
> (and sorry for the delay in my reply!)
>
> So, from the discussion thread and some IRC chat with Jeff, I'm sending
> v2. What changed? Everything! :-)
>
> - Use i_count instead of __ceph_is_file_opened to check for open files
> - Add call to ceph_do_getattr to make sure we have LINK caps before
> accessing i_nlink
>
> Cheers,
> --
> Luis
Acked-by: Amir Goldstein <amir73il@xxxxxxxxx>
Thanks,
Amir.
