Skip to content
Commit 43a08c3b authored by Ziyang Xuan's avatar Ziyang Xuan Committed by Marc Kleine-Budde
Browse files

can: isotp: isotp_sendmsg(): fix TX buffer concurrent access in isotp_sendmsg()

When isotp_sendmsg() concurrent, tx.state of all TX processes can be
ISOTP_IDLE. The conditions so->tx.state != ISOTP_IDLE and
wq_has_sleeper(&so->wait) can not protect TX buffer from being
accessed by multiple TX processes.

We can use cmpxchg() to try to modify tx.state to ISOTP_SENDING firstly.
If the modification of the previous process succeed, the later process
must wait tx.state to ISOTP_IDLE firstly. Thus, we can ensure TX buffer
is accessed by only one process at the same time. And we should also
restore the original tx.state at the subsequent error processes.

Fixes: e057dd3f ("can: add ISO 15765-2:2016 transport protocol")
Link: https://lore.kernel.org/all/c2517874fbdf4188585cf9ddf67a8fa74d5dbde5.1633764159.git.william.xuanziyang@huawei.com


Cc: stable@vger.kernel.org
Signed-off-by: default avatarZiyang Xuan <william.xuanziyang@huawei.com>
Acked-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 9acf6362
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment