[PATCH net 3/4] can: j1939: abort multipacket broadcast session when timeout occurs

[Zhang Changzhong]

If timeout occurs, j1939_tp_rxtimer() first calls hrtimer_start() to
restart rxtimer, and then calls __j1939_session_cancel() to set
session->state = J1939_SESSION_WAITING_ABORT. At next timeout
expiration, because of the J1939_SESSION_WAITING_ABORT session state
j1939_tp_rxtimer() will call j1939_session_deactivate_activate_next()
to deactivate current session, and rxtimer won't be set.

But for multipacket broadcast session, __j1939_session_cancel() don't
set session->state = J1939_SESSION_WAITING_ABORT, thus current session
won't be deactivate and hrtimer_start() is called to start new
rxtimer again and again.

So fix it by moving session->state = J1939_SESSION_WAITING_ABORT out of
if (!j1939_cb_is_broadcast(&session->skcb)) statement.

Fixes: 9d71dd0c7009 ("can: add support of SAE J1939 protocol")
Signed-off-by: Zhang Changzhong <zhangchangzh...@huawei.com>
---
 net/can/j1939/transport.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/can/j1939/transport.c b/net/can/j1939/transport.c
index dd6a120..5757f9f 100644
--- a/net/can/j1939/transport.c
+++ b/net/can/j1939/transport.c
@@ -1055,9 +1055,9 @@ static void __j1939_session_cancel(struct j1939_session 
*session,
        lockdep_assert_held(&session->priv->active_session_list_lock);
 
        session->err = j1939_xtp_abort_to_errno(priv, err);
+       session->state = J1939_SESSION_WAITING_ABORT;
        /* do not send aborts on incoming broadcasts */
        if (!j1939_cb_is_broadcast(&session->skcb)) {
-               session->state = J1939_SESSION_WAITING_ABORT;
                j1939_xtp_tx_abort(priv, &session->skcb,
                                   !session->transmission,
                                   err, session->skcb.addr.pgn);
-- 
2.9.5