NOPIN response timer may expire on a deleted connection and crash with such logs: Did not receive response to NOPIN on CID: 0, failing connection for I_T Nexus (null),i,0x00023d000125,iqn.2017-01.com.iscsi.target,t,0x3d BUG: Kernel NULL pointer dereference on read at 0x00000000 NIP strlcpy+0x8/0xb0 LR iscsit_fill_cxn_timeout_err_stats+0x5c/0xc0 [iscsi_target_mod] Call Trace: iscsit_handle_nopin_response_timeout+0xfc/0x120 [iscsi_target_mod] call_timer_fn+0x58/0x1f0 run_timer_softirq+0x740/0x860 __do_softirq+0x16c/0x420 irq_exit+0x188/0x1c0 timer_interrupt+0x184/0x410 That is because nopin response timer may be re-started on nopin timer expiration. Stop nopin timer before stopping the nopin response timer to be sure that no one of them will be re-started. Signed-off-by: Dmitry Bogdanov <d.bogdanov@xxxxxxxxx> --- drivers/target/iscsi/iscsi_target.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 6002283cbeba..68bbdf3ee101 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -4317,8 +4317,8 @@ int iscsit_close_connection( spin_unlock(&iscsit_global->ts_bitmap_lock); iscsit_stop_timers_for_cmds(conn); - iscsit_stop_nopin_response_timer(conn); iscsit_stop_nopin_timer(conn); + iscsit_stop_nopin_response_timer(conn); if (conn->conn_transport->iscsit_wait_conn) conn->conn_transport->iscsit_wait_conn(conn); -- 2.25.1
