From a3335faebe1608f3e78e24f09501c9f7d5ebf87a Mon Sep 17 00:00:00 2001
From: Chen Zhongjin <chenzhongjin@huawei.com>
Date: Mon, 31 Oct 2022 11:30:53 +0800
Subject: [PATCH] can: af_can: can_exit(): add missing dev_remove_pack() of
 canxl_packet

In can_init(), dev_add_pack(&canxl_packet) is added but not removed in
can_exit(). It breaks the packet handler list and can make kernel
panic when can_init() is called for the second time.

| > modprobe can && rmmod can
| > rmmod xxx && modprobe can
|
| BUG: unable to handle page fault for address: fffffbfff807d7f4
| RIP: 0010:dev_add_pack+0x133/0x1f0
| Call Trace:
|  <TASK>
|  can_init+0xaa/0x1000 [can]
|  do_one_initcall+0xd3/0x4e0
|  ...

Fixes: fb08cba12b52 ("can: canxl: update CAN infrastructure for CAN XL frames")
Signed-off-by: Chen Zhongjin <chenzhongjin@huawei.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20221031033053.37849-1-chenzhongjin@huawei.com
[mkl: adjust subject and commit message]
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
---
 net/can/af_can.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/net/can/af_can.c b/net/can/af_can.c
index 9503ab10f9b8f..5e9e3e1e9825f 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -902,6 +902,7 @@ static __init int can_init(void)
 static __exit void can_exit(void)
 {
 	/* protocol unregister */
+	dev_remove_pack(&canxl_packet);
 	dev_remove_pack(&canfd_packet);
 	dev_remove_pack(&can_packet);
 	sock_unregister(PF_CAN);