From: Jia Guo guojia12@huawei.com
[ Upstream commit cc725ef3cb202ef2019a3c67c8913efa05c3cce6 ]
In the process of creating a node, it will cause NULL pointer dereference in kernel if o2cb_ctl failed in the interval (mkdir, o2cb_set_node_attribute(node_num)] in function o2cb_add_node.
The node num is initialized to 0 in function o2nm_node_group_make_item, o2nm_node_group_drop_item will mistake the node number 0 for a valid node number when we delete the node before the node number is set correctly. If the local node number of the current host happens to be 0, cluster->cl_local_node will be set to O2NM_INVALID_NODE_NUM while o2hb_thread still running. The panic stack is generated as follows:
o2hb_thread -o2hb_do_disk_heartbeat -o2hb_check_own_slot |-slot = ®->hr_slots[o2nm_this_node()]; //o2nm_this_node() return O2NM_INVALID_NODE_NUM
We need to check whether the node number is set when we delete the node.
Link: http://lkml.kernel.org/r/133d8045-72cc-863e-8eae-5013f9f6bc51@huawei.com Signed-off-by: Jia Guo guojia12@huawei.com Reviewed-by: Joseph Qi jiangqi903@gmail.com Acked-by: Jun Piao piaojun@huawei.com Cc: Mark Fasheh mark@fasheh.com Cc: Joel Becker jlbec@evilplan.org Cc: Junxiao Bi junxiao.bi@oracle.com Cc: Changwei Ge ge.changwei@h3c.com Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- fs/ocfs2/cluster/nodemanager.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/fs/ocfs2/cluster/nodemanager.c b/fs/ocfs2/cluster/nodemanager.c index 441c84e169e6..059414bb19dc 100644 --- a/fs/ocfs2/cluster/nodemanager.c +++ b/fs/ocfs2/cluster/nodemanager.c @@ -721,13 +721,15 @@ static void o2nm_node_group_drop_item(struct config_group *group, struct o2nm_node *node = to_o2nm_node(item); struct o2nm_cluster *cluster = to_o2nm_cluster(group->cg_item.ci_parent);
- o2net_disconnect_node(node); + if (cluster->cl_nodes[node->nd_num] == node) { + o2net_disconnect_node(node);
- if (cluster->cl_has_local && - (cluster->cl_local_node == node->nd_num)) { - cluster->cl_has_local = 0; - cluster->cl_local_node = O2NM_INVALID_NODE_NUM; - o2net_stop_listening(node); + if (cluster->cl_has_local && + (cluster->cl_local_node == node->nd_num)) { + cluster->cl_has_local = 0; + cluster->cl_local_node = O2NM_INVALID_NODE_NUM; + o2net_stop_listening(node); + } }
/* XXX call into net to stop this node from trading messages */