[PATCH 2/5] afs: Make error on cell lookup failure consistent with OpenAFS

[Marc Dionne]

On Thu, Nov 16, 2023 at 11:53 AM David Howells <dhowells at redhat.com> wrote:
>
> When kafs tries to look up a cell in the DNS or the local config, it will
> translate a lookup failure into EDESTADDRREQ whereas OpenAFS translates it
> into ENOENT.  Applications such as West expect the latter behaviour and
> fail if they see the former.
>
> This can be seen by trying to mount an unknown cell:
>
>    # mount -t afs %example.com:cell.root /mnt
>    mount: /mnt: mount(2) system call failed: Destination address required.
>
> Fixes: 4d673da14533 ("afs: Support the AFS dynamic root")
> Reported-by: Markus Suvanto <markus.suvanto at gmail.com>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216637
> Signed-off-by: David Howells <dhowells at redhat.com>
> Reviewed-by: Jeffrey Altman <jaltman at auristor.com>
> cc: Marc Dionne <marc.dionne at auristor.com>
> cc: linux-afs at lists.infradead.org
> ---
>  fs/afs/dynroot.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/fs/afs/dynroot.c b/fs/afs/dynroot.c
> index 4d04ef2d3ae7..1fa8cf23bd36 100644
> --- a/fs/afs/dynroot.c
> +++ b/fs/afs/dynroot.c
> @@ -132,8 +132,8 @@ static int afs_probe_cell_name(struct dentry *dentry)
>
>         ret = dns_query(net->net, "afsdb", name, len, "srv=1",
>                         NULL, NULL, false);
> -       if (ret == -ENODATA)
> -               ret = -EDESTADDRREQ;
> +       if (ret == -ENODATA || ret == -ENOKEY)
> +               ret = -ENOENT;
>         return ret;
>  }

Reviewed-by: Marc Dionne <marc.dionne at auristor.com>

Marc