iscsi_tcp: consider session state in iscsi_sw_sk_state_check

It seems some iSCSI targets (including the Linux kernel target) close the TCP connection from the target side immediately after processing a session logout.

When a TCP FIN comes in right after the iSCSI logout response, iscsi_sw_sk_state_check sees the local socket as not yet being in CLOSE_WAIT or CLOSE and logs an error. But the initiator would close the connection right after processing the logout response anyway, and the error is confusing to admins who just requested that the session be shut down.

This adds a check of the session state, and suppresses the error if we are in the process of logging out.

---
 drivers/scsi/iscsi_tcp.c | 1 +
 1 file changed, 1 insertion(+)

index 9e2588a..add6d15 100644
@@ -116,6 +116,7 @@ static inline int iscsi_sw_sk_state_check(struct sock *sk)
 	struct iscsi_conn *conn = sk->sk_user_data;
 
 	if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) &&
+	    (conn->session->state != ISCSI_STATE_LOGGING_OUT) &&
 	    !atomic_read(&sk->sk_rmem_alloc)) {
 		ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n");
 		iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE);

1.8.3.1