From 21aaa23b0ebbd19334fa461370c03cbb076b3295 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Thu, 7 Jan 2016 22:09:27 -0800 Subject: target: Obtain se_node_acl->acl_kref during get_initiator_node_acl This patch addresses a long standing race where obtaining se_node_acl->acl_kref in __transport_register_session() happens a bit too late, and leaves open the potential for core_tpg_del_initiator_node_acl() to hit a NULL pointer dereference. Instead, take ->acl_kref in core_tpg_get_initiator_node_acl() while se_portal_group->acl_node_mutex is held, and move the final target_put_nacl() from transport_deregister_session() into transport_free_session() so that fabric driver login failure handling using the modern method to still work as expected. Also, update core_tpg_get_initiator_node_acl() to take an extra reference for dynamically generated acls for demo-mode, before returning to fabric caller. Also update iscsi-target sendtargets special case handling to use target_tpg_has_node_acl() when checking if demo_mode_discovery == true during discovery lookup. Note the existing wait_for_completion(&acl->acl_free_comp) in core_tpg_del_initiator_node_acl() does not change. Cc: Sagi Grimberg Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Andy Grover Cc: Mike Christie Signed-off-by: Nicholas Bellinger --- drivers/target/iscsi/iscsi_target.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/target/iscsi') diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index a81c0e5ca293..762b2d6ea1cc 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -3435,7 +3435,7 @@ iscsit_build_sendtargets_response(struct iscsi_cmd *cmd, if ((tpg->tpg_attrib.generate_node_acls == 0) && (tpg->tpg_attrib.demo_mode_discovery == 0) && - (!core_tpg_get_initiator_node_acl(&tpg->tpg_se_tpg, + (!target_tpg_has_node_acl(&tpg->tpg_se_tpg, cmd->conn->sess->sess_ops->InitiatorName))) { continue; } -- cgit v1.2.3