From 13247018d68f21e7132924b9853f7e2c423588b6 Mon Sep 17 00:00:00 2001 From: Maurizio Lombardi Date: Mon, 8 May 2023 18:22:17 +0200 Subject: scsi: target: iscsi: Fix hang in the iSCSI login code If the initiator suddenly stops sending data during a login while keeping the TCP connection open, the login_work won't be scheduled and will never release the login semaphore; concurrent login operations will therefore get stuck and fail. The bug is due to the inability of the login timeout code to properly handle this particular case. Fix the problem by replacing the old per-NP login timer with a new per-connection timer. The timer is started when an initiator connects to the target; if it expires, it sends a SIGINT signal to the thread pointed at by the conn->login_kworker pointer. conn->login_kworker is set by calling the iscsit_set_login_timer_kworker() helper, initially it will point to the np thread; When the login operation's control is in the process of being passed from the NP-thread to login_work, the conn->login_worker pointer is set to NULL. Finally, login_kworker will be changed to point to the worker thread executing the login_work job. If conn->login_kworker is NULL when the timer expires, it means that the login operation hasn't been completed yet but login_work isn't running, in this case the timer will mark the login process as failed and will schedule login_work so the latter will be forced to free the resources it holds. Signed-off-by: Maurizio Lombardi Link: https://lore.kernel.org/r/20230508162219.1731964-2-mlombard@redhat.com Reviewed-by: Mike Christie Signed-off-by: Martin K. Petersen --- drivers/target/iscsi/iscsi_target.c | 2 -- 1 file changed, 2 deletions(-) (limited to 'drivers/target/iscsi/iscsi_target.c') diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 834cce50f9b0..b516c2893420 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -364,8 +364,6 @@ struct iscsi_np *iscsit_add_np( init_completion(&np->np_restart_comp); INIT_LIST_HEAD(&np->np_list); - timer_setup(&np->np_login_timer, iscsi_handle_login_thread_timeout, 0); - ret = iscsi_target_setup_login_socket(np, sockaddr); if (ret != 0) { kfree(np); -- cgit v1.2.3