Zhang Changzhong b9c4a9a07c can: j1939: j1939_sk_bind(): return failure if netdev is down ... [ Upstream commit 08c487d8d8 ] When a netdev down event occurs after a successful call to j1939_sk_bind(), j1939_netdev_notify() can handle it correctly. But if the netdev already in down state before calling j1939_sk_bind(), j1939_sk_release() will stay in wait_event_interruptible() blocked forever. Because in this case, j1939_netdev_notify() won't be called and j1939_tp_txtimer() won't call j1939_session_cancel() or other function to clear session for ENETDOWN error, this lead to mismatch of j1939_session_get/put() and jsk->skb_pending will never decrease to zero. To reproduce it use following commands: 1. ip link add dev vcan0 type vcan 2. j1939acd -r 100,80-120 1122334455667788 vcan0 3. presses ctrl-c and thread will be blocked forever This patch adds check for ndev->flags in j1939_sk_bind() to avoid this kind of situation and return with -ENETDOWN. Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol") Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> Link: https://lore.kernel.org/r/1599460308-18770-1-git-send-email-zhangchangzhong@huawei.com Acked-by: Oleksij Rempel <o.rempel@pengutronix.de> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-11-18 19:20:19 +01:00
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Kconfig	can: add support of SAE J1939 protocol	2019-09-04 14:22:33 +02:00
Makefile	can: add support of SAE J1939 protocol	2019-09-04 14:22:33 +02:00
address-claim.c	can: add support of SAE J1939 protocol	2019-09-04 14:22:33 +02:00
bus.c	can: add support of SAE J1939 protocol	2019-09-04 14:22:33 +02:00
j1939-priv.h	can: add support of SAE J1939 protocol	2019-09-04 14:22:33 +02:00
main.c	can: j1939: warn if resources are still linked on destroy	2019-11-13 10:42:34 +01:00
socket.c	can: j1939: j1939_sk_bind(): return failure if netdev is down	2020-11-18 19:20:19 +01:00
transport.c	net: j1939: j1939_session_fresh_new(): fix missing initialization of skbcnt	2020-10-29 09:57:24 +01:00