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 --- include/target/target_core_fabric.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/target') diff --git a/include/target/target_core_fabric.h b/include/target/target_core_fabric.h index 48e002f86893..56653408f53b 100644 --- a/include/target/target_core_fabric.h +++ b/include/target/target_core_fabric.h @@ -169,6 +169,8 @@ void core_allocate_nexus_loss_ua(struct se_node_acl *acl); struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg, unsigned char *); +bool target_tpg_has_node_acl(struct se_portal_group *tpg, + const char *); struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *, unsigned char *); int core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32); -- cgit v1.2.3