Re: [PATCH 5.12 083/161] libceph: dont set global_id until we get an auth ticket

[Ilya Dryomov]

On Tue, Jun 8, 2021 at 9:24 PM Sasha Levin <sashal@xxxxxxxxxx> wrote:
>
> On Tue, Jun 08, 2021 at 09:07:18PM +0200, Ilya Dryomov wrote:
> >On Tue, Jun 8, 2021 at 8:48 PM Greg Kroah-Hartman
> ><gregkh@xxxxxxxxxxxxxxxxxxx> wrote:
> >>
> >> From: Ilya Dryomov <idryomov@xxxxxxxxx>
> >>
> >> [ Upstream commit 61ca49a9105faefa003b37542cebad8722f8ae22 ]
> >>
> >> With the introduction of enforcing mode, setting global_id as soon
> >> as we get it in the first MAuth reply will result in EACCES if the
> >> connection is reset before we get the second MAuth reply containing
> >> an auth ticket -- because on retry we would attempt to reclaim that
> >> global_id with no auth ticket at hand.
> >>
> >> Neither ceph_auth_client nor ceph_mon_client depend on global_id
> >> being set ealy, so just delay the setting until we get and process
> >> the second MAuth reply.  While at it, complain if the monitor sends
> >> a zero global_id or changes our global_id as the session is likely
> >> to fail after that.
> >>
> >> Cc: stable@xxxxxxxxxxxxxxx # needs backporting for < 5.11
> >> Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
> >> Reviewed-by: Sage Weil <sage@xxxxxxxxxx>
> >> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> >> ---
> >>  net/ceph/auth.c | 36 +++++++++++++++++++++++-------------
> >>  1 file changed, 23 insertions(+), 13 deletions(-)
> >>
> >> diff --git a/net/ceph/auth.c b/net/ceph/auth.c
> >> index eb261aa5fe18..de407e8feb97 100644
> >> --- a/net/ceph/auth.c
> >> +++ b/net/ceph/auth.c
> >> @@ -36,6 +36,20 @@ static int init_protocol(struct ceph_auth_client *ac, int proto)
> >>         }
> >>  }
> >>
> >> +static void set_global_id(struct ceph_auth_client *ac, u64 global_id)
> >> +{
> >> +       dout("%s global_id %llu\n", __func__, global_id);
> >> +
> >> +       if (!global_id)
> >> +               pr_err("got zero global_id\n");
> >> +
> >> +       if (ac->global_id && global_id != ac->global_id)
> >> +               pr_err("global_id changed from %llu to %llu\n", ac->global_id,
> >> +                      global_id);
> >> +
> >> +       ac->global_id = global_id;
> >> +}
> >> +
> >>  /*
> >>   * setup, teardown.
> >>   */
> >> @@ -222,11 +236,6 @@ int ceph_handle_auth_reply(struct ceph_auth_client *ac,
> >>
> >>         payload_end = payload + payload_len;
> >>
> >> -       if (global_id && ac->global_id != global_id) {
> >> -               dout(" set global_id %lld -> %lld\n", ac->global_id, global_id);
> >> -               ac->global_id = global_id;
> >> -       }
> >> -
> >>         if (ac->negotiating) {
> >>                 /* server does not support our protocols? */
> >>                 if (!protocol && result < 0) {
> >> @@ -253,11 +262,16 @@ int ceph_handle_auth_reply(struct ceph_auth_client *ac,
> >>
> >>         ret = ac->ops->handle_reply(ac, result, payload, payload_end,
> >>                                     NULL, NULL, NULL, NULL);
> >> -       if (ret == -EAGAIN)
> >> +       if (ret == -EAGAIN) {
> >>                 ret = build_request(ac, true, reply_buf, reply_len);
> >> -       else if (ret)
> >> +               goto out;
> >> +       } else if (ret) {
> >>                 pr_err("auth protocol '%s' mauth authentication failed: %d\n",
> >>                        ceph_auth_proto_name(ac->protocol), result);
> >> +               goto out;
> >> +       }
> >> +
> >> +       set_global_id(ac, global_id);
> >>
> >>  out:
> >>         mutex_unlock(&ac->mutex);
> >> @@ -484,15 +498,11 @@ int ceph_auth_handle_reply_done(struct ceph_auth_client *ac,
> >>         int ret;
> >>
> >>         mutex_lock(&ac->mutex);
> >> -       if (global_id && ac->global_id != global_id) {
> >> -               dout("%s global_id %llu -> %llu\n", __func__, ac->global_id,
> >> -                    global_id);
> >> -               ac->global_id = global_id;
> >> -       }
> >> -
> >>         ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
> >>                                     session_key, session_key_len,
> >>                                     con_secret, con_secret_len);
> >> +       if (!ret)
> >> +               set_global_id(ac, global_id);
> >>         mutex_unlock(&ac->mutex);
> >>         return ret;
> >>  }
> >
> >Hi Greg,
> >
> >I asked Sasha to drop this patch earlier today.
>
> I've dropped it now, but I think I'm missing your previous request. Was
> it as a reply to the added-to mail? I just want to make sure I'm not
> missing your mails.

Yes, but it looks like it didn't make it to stable-commits mailing list
either.  Weird...

    MIME-Version: 1.0
    Date: Tue, 8 Jun 2021 11:13:08 +0200
    References: <20210608011339.51B0F6124C@xxxxxxxxxxxxxxx>
    In-Reply-To: <20210608011339.51B0F6124C@xxxxxxxxxxxxxxx>
    Message-ID:
<CAOi1vP9Ubs1Cu6sW43H-=dVXSzkFZBycfR_Af4b3vJ9mihkAzA@xxxxxxxxxxxxxx>
    Subject: Re: Patch "libceph: don't set global_id until we get an
auth ticket" has been added to the 5.12-stable tree
    From: Ilya Dryomov <idryomov@xxxxxxxxx>
    To: Sasha Levin <sashal@xxxxxxxxxx>
    Cc: stable-commits@xxxxxxxxxxxxxxx
    Content-Type: text/plain; charset="UTF-8"

Thanks,

                Ilya