can: j1939: change j1939_netdev_lock type to mutex

Browse source

commit cd9c790de2 upstream.

It turns out access to j1939_can_rx_register() needs to be serialized,
otherwise j1939_priv can be corrupted when parallel threads call
j1939_netdev_start() and j1939_can_rx_register() fails. This issue is
thoroughly covered in other commit which serializes access to
j1939_can_rx_register().

Change j1939_netdev_lock type to mutex so that we do not need to remove
GFP_KERNEL from can_rx_register().

j1939_netdev_lock seems to be used in normal contexts where mutex usage
is not prohibited.

Found by Linux Verification Center (linuxtesting.org) with Syzkaller.

Fixes: 9d71dd0c70 ("can: add support of SAE J1939 protocol")
Suggested-by: Alexey Khoroshilov <khoroshilov@ispras.ru>
Signed-off-by: Fedor Pchelkin <pchelkin@ispras.ru>
Tested-by: Oleksij Rempel <o.rempel@pengutronix.de>
Acked-by: Oleksij Rempel <o.rempel@pengutronix.de>
Link: https://lore.kernel.org/r/20230526171910.227615-2-pchelkin@ispras.ru
Cc: stable@vger.kernel.org
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

...

This commit is contained in:

Fedor Pchelkin 2023-05-26 20:19:09 +03:00 • committed by Greg Kroah-Hartman

parent e2a6db7cab

commit 67eb5a5153

1 changed files with 11 additions and 11 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

22

net/can/j1939/main.c

View file