Re: [PATCH 3/5] afs: Return ENOENT if no cell DNS record can be found

[Marc Dionne]

On Thu, Nov 16, 2023 at 11:53 AM David Howells <dhowells@xxxxxxxxxx> wrote:
>
> Make AFS return error ENOENT if no cell SRV or AFSDB DNS record (or
> cellservdb config file record) can be found rather than returning
> EDESTADDRREQ.
>
> Also add cell name lookup info to the cursor dump.
>
> Fixes: d5c32c89b208 ("afs: Fix cell DNS lookup")
> Reported-by: Markus Suvanto <markus.suvanto@xxxxxxxxx>
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216637
> Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
> cc: Marc Dionne <marc.dionne@xxxxxxxxxxxx>
> cc: linux-afs@xxxxxxxxxxxxxxxxxxx
> ---
>  fs/afs/vl_rotate.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/fs/afs/vl_rotate.c b/fs/afs/vl_rotate.c
> index 488e58490b16..eb415ce56360 100644
> --- a/fs/afs/vl_rotate.c
> +++ b/fs/afs/vl_rotate.c
> @@ -58,6 +58,12 @@ static bool afs_start_vl_iteration(struct afs_vl_cursor *vc)
>                 }
>
>                 /* Status load is ordered after lookup counter load */
> +               if (cell->dns_status == DNS_LOOKUP_GOT_NOT_FOUND) {
> +                       pr_warn("No record of cell %s\n", cell->name);
> +                       vc->error = -ENOENT;
> +                       return false;
> +               }
> +
>                 if (cell->dns_source == DNS_RECORD_UNAVAILABLE) {
>                         vc->error = -EDESTADDRREQ;
>                         return false;
> @@ -285,6 +291,7 @@ bool afs_select_vlserver(struct afs_vl_cursor *vc)
>   */
>  static void afs_vl_dump_edestaddrreq(const struct afs_vl_cursor *vc)
>  {
> +       struct afs_cell *cell = vc->cell;
>         static int count;
>         int i;
>
> @@ -294,6 +301,9 @@ static void afs_vl_dump_edestaddrreq(const struct afs_vl_cursor *vc)
>
>         rcu_read_lock();
>         pr_notice("EDESTADDR occurred\n");
> +       pr_notice("CELL: %s err=%d\n", cell->name, cell->error);
> +       pr_notice("DNS: src=%u st=%u lc=%x\n",
> +                 cell->dns_source, cell->dns_status, cell->dns_lookup_count);
>         pr_notice("VC: ut=%lx ix=%u ni=%hu fl=%hx err=%hd\n",
>                   vc->untried, vc->index, vc->nr_iterations, vc->flags, vc->error);

Reviewed-by: Marc Dionne <marc.dionne@xxxxxxxxxxxx>

Marc