From: Jia Guo Date: Tue, 5 Mar 2019 23:41:41 +0000 (-0800) Subject: ocfs2: fix a panic problem caused by o2cb_ctl X-Git-Tag: v4.19.34~155 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=20141feb9bdec6e7daed7782c1535b31081aeb71;p=platform%2Fkernel%2Flinux-rpi.git ocfs2: fix a panic problem caused by o2cb_ctl [ 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 Reviewed-by: Joseph Qi Acked-by: Jun Piao Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Changwei Ge Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- diff --git a/fs/ocfs2/cluster/nodemanager.c b/fs/ocfs2/cluster/nodemanager.c index 0e4166c..4ac775e 100644 --- a/fs/ocfs2/cluster/nodemanager.c +++ b/fs/ocfs2/cluster/nodemanager.c @@ -621,13 +621,15 @@ 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 */