From: David Teigland <teigland@redhat.com>
Date: Thu, 5 Jun 2008 14:10:29 -0500
Subject: [dlm] reject messages from non-members
Message-id: 20080605191029.GH18635@redhat.com
O-Subject: [RHEL5.3 PATCH 08/18] dlm: reject messages from non-members
Bugzilla: 450132
RH-Acked-by: Bob Peterson <rpeterso@redhat.com>

bz 450132  dlm: fixes for recovery of user lockspace

Fix bugs when userland apps using the dlm join/leave the lockspace,
causing recovery.

brew build including this patch
http://brewweb.devel.redhat.com/brew/taskinfo?taskID=1344633

upstream commit:

>From 46b43eed7018bab3a4e8c259eed27697b9170cb8 Mon Sep 17 00:00:00 2001
>From: David Teigland <teigland@redhat.com>
>Date: Tue, 8 Jan 2008 16:24:00 -0600
>Subject: [PATCH] dlm: reject messages from non-members

Messages from nodes that are no longer members of the lockspace should be
ignored.  When nodes are removed from the lockspace, recovery can
sometimes complete quickly enough that messages arrive from a removed node
after recovery has completed.  When processed, these messages would often
cause an error message, and could in some cases change some state, causing
problems.

Signed-off-by: David Teigland <teigland@redhat.com>

diff --git a/fs/dlm/lock.c b/fs/dlm/lock.c
index 37a2988..c95101e 100644
--- a/fs/dlm/lock.c
+++ b/fs/dlm/lock.c
@@ -1,7 +1,7 @@
 /******************************************************************************
 *******************************************************************************
 **
-**  Copyright (C) 2005-2007 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2005-2008 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -3644,6 +3644,13 @@ static void receive_lookup_reply(struct dlm_ls *ls, struct dlm_message *ms)
 
 static void _receive_message(struct dlm_ls *ls, struct dlm_message *ms)
 {
+	if (!dlm_is_member(ls, ms->m_header.h_nodeid)) {
+		log_debug(ls, "ignore non-member message %d from %d %x %x %d",
+			  ms->m_type, ms->m_header.h_nodeid, ms->m_lkid,
+			  ms->m_remid, ms->m_result);
+		return;
+	}
+
 	switch (ms->m_type) {
 
 	/* messages sent to a master node */
diff --git a/fs/dlm/member.c b/fs/dlm/member.c
index e9cdcab..fa17f5a 100644
--- a/fs/dlm/member.c
+++ b/fs/dlm/member.c
@@ -1,7 +1,7 @@
 /******************************************************************************
 *******************************************************************************
 **
-**  Copyright (C) 2005-2007 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2005-2008 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -70,7 +70,7 @@ static void dlm_remove_member(struct dlm_ls *ls, struct dlm_member *memb)
 	ls->ls_num_nodes--;
 }
 
-static int dlm_is_member(struct dlm_ls *ls, int nodeid)
+int dlm_is_member(struct dlm_ls *ls, int nodeid)
 {
 	struct dlm_member *memb;
 
diff --git a/fs/dlm/member.h b/fs/dlm/member.h
index 927c08c..7a26fca 100644
--- a/fs/dlm/member.h
+++ b/fs/dlm/member.h
@@ -1,7 +1,7 @@
 /******************************************************************************
 *******************************************************************************
 **
-**  Copyright (C) 2005 Red Hat, Inc.  All rights reserved.
+**  Copyright (C) 2005-2008 Red Hat, Inc.  All rights reserved.
 **
 **  This copyrighted material is made available to anyone wishing to use,
 **  modify, copy, or redistribute it subject to the terms and conditions
@@ -19,6 +19,7 @@ void dlm_clear_members(struct dlm_ls *ls);
 void dlm_clear_members_gone(struct dlm_ls *ls);
 int dlm_recover_members(struct dlm_ls *ls, struct dlm_recover *rv,int *neg_out);
 int dlm_is_removed(struct dlm_ls *ls, int nodeid);
+int dlm_is_member(struct dlm_ls *ls, int nodeid);
 
 #endif                          /* __MEMBER_DOT_H__ */