On 21.06.2021 13:24:51, Marc Kleine-Budde wrote:
> From: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
> 
> commit 8d0caedb759683041d9db82069937525999ada53 upstream
> 
> syzbot is reporting hung task at register_netdevice_notifier() [1] and
> unregister_netdevice_notifier() [2], for cleanup_net() might perform
> time consuming operations while CAN driver's raw/bcm/isotp modules are
> calling {register,unregister}_netdevice_notifier() on each socket.
> 
> Change raw/bcm/isotp modules to call register_netdevice_notifier() from
> module's __init function and call unregister_netdevice_notifier() from
> module's __exit function, as with gw/j1939 modules are doing.
> 
> Link: https://syzkaller.appspot.com/bug?id=391b9498827788b3cc6830226d4ff5be87107c30 [1]
> Link: https://syzkaller.appspot.com/bug?id=1724d278c83ca6e6df100a2e320c10d991cf2bce [2]
> Link: https://lore.kernel.org/r/54a5f451-05ed-f977-8534-79e7aa2bcc8f@i-love.sakura.ne.jp
> Cc: linux-stable <stable@vger.kernel.org>
> Reported-by: syzbot <syzbot+355f8edb2ff45d5f95fa@syzkaller.appspotmail.com>
> Reported-by: syzbot <syzbot+0f1827363a305f74996f@syzkaller.appspotmail.com>
> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
> Tested-by: syzbot <syzbot+355f8edb2ff45d5f95fa@syzkaller.appspotmail.com>
> Tested-by: Oliver Hartkopp <socketcan@hartkopp.net>
> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
> [mkl: ported to v4.19.195]
> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
> ---
> Hello Greg,
> 
> this is a backport of
> 
> | 8d0caedb7596 can: bcm/raw/isotp: use per module netdevice notifier
> 
> to v4.19.195. Please apply.

This also applies to v4.14.237.

I'm working on a v4.9 version.

Marc

-- 
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