Patch "libceph: don't set global_id until we get an auth ticket" has been added to the 5.12-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    libceph: don't set global_id until we get an auth ticket

to the 5.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     libceph-don-t-set-global_id-until-we-get-an-auth-tic.patch
and it can be found in the queue-5.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit c2e1ce527ba85e212a22a854d261db4804f94598
Author: Ilya Dryomov <idryomov@xxxxxxxxx>
Date:   Mon Apr 26 19:11:37 2021 +0200

    libceph: don't set global_id until we get an auth ticket
    
    [ 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>

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;
 }