• Xin Long's avatar
    sctp: allow delivering notifications after receiving SHUTDOWN · a0fc6843
    Xin Long authored
    Prior to this patch, once sctp received SHUTDOWN or shutdown with RD,
    sk->sk_shutdown would be set with RCV_SHUTDOWN, and all events would
    be dropped in sctp_ulpq_tail_event(). It would cause:
    
    1. some notifications couldn't be received by users. like
       SCTP_SHUTDOWN_COMP generated by sctp_sf_do_4_C().
    
    2. sctp would also never trigger sk_data_ready when the association
       was closed, making it harder to identify the end of the association
       by calling recvmsg() and getting an EOF. It was not convenient for
       kernel users.
    
    The check here should be stopping delivering DATA chunks after receiving
    SHUTDOWN, and stopping delivering ANY chunks after sctp_close().
    
    So this patch is to allow notifications to enqueue into receive queue
    even if sk->sk_shutdown is set to RCV_SHUTDOWN in sctp_ulpq_tail_event,
    but if sk->sk_shutdown == RCV_SHUTDOWN | SEND_SHUTDOWN, it drops all
    events.
    Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
    Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    a0fc6843
ulpqueue.c 29.2 KB