3.12-stable review patch. If anyone has any objections, please let me know.
------------------ From: Nicholas Bellinger <[email protected]> commit db6077fd0b7dd41dc6ff18329cec979379071f87 upstream. When shutting down a target there is a race condition between iscsit_del_np() and __iscsi_target_login_thread(). The latter sets the thread pointer to NULL, and the former tries to issue kthread_stop() on that pointer without any synchronization. This patch moves the np->np_thread NULL assignment into iscsit_del_np(), after kthread_stop() has completed. It also removes the signal_pending() + np_state check, and only exits when kthread_should_stop() is true. Reported-by: Hannes Reinecke <[email protected]> Signed-off-by: Nicholas Bellinger <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/target/iscsi/iscsi_target.c | 1 + drivers/target/iscsi/iscsi_target_login.c | 6 ------ 2 files changed, 1 insertion(+), 6 deletions(-) --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -465,6 +465,7 @@ int iscsit_del_np(struct iscsi_np *np) */ send_sig(SIGINT, np->np_thread, 1); kthread_stop(np->np_thread); + np->np_thread = NULL; } np->np_transport->iscsit_free_np(np); --- a/drivers/target/iscsi/iscsi_target_login.c +++ b/drivers/target/iscsi/iscsi_target_login.c @@ -1404,11 +1404,6 @@ old_sess_out: out: stop = kthread_should_stop(); - if (!stop && signal_pending(current)) { - spin_lock_bh(&np->np_thread_lock); - stop = (np->np_thread_state == ISCSI_NP_THREAD_SHUTDOWN); - spin_unlock_bh(&np->np_thread_lock); - } /* Wait for another socket.. */ if (!stop) return 1; @@ -1416,7 +1411,6 @@ exit: iscsi_stop_login_thread_timer(np); spin_lock_bh(&np->np_thread_lock); np->np_thread_state = ISCSI_NP_THREAD_EXIT; - np->np_thread = NULL; spin_unlock_bh(&np->np_thread_lock); return 0; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
