[PATCH AUTOSEL 5.1 40/95] can: af_can: Fix error path of can_init()

From: Sasha Levin
Date: Wed Jun 26 2019 - 20:53:29 EST


From: YueHaibing <yuehaibing@xxxxxxxxxx>

[ Upstream commit c5a3aed1cd3152429348ee1fe5cdcca65fe901ce ]

This patch add error path for can_init() to avoid possible crash if some
error occurs.

Fixes: 0d66548a10cb ("[CAN]: Add PF_CAN core module")
Signed-off-by: YueHaibing <yuehaibing@xxxxxxxxxx>
Acked-by: Oliver Hartkopp <socketcan@xxxxxxxxxxxx>
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
net/can/af_can.c | 24 +++++++++++++++++++++---
1 file changed, 21 insertions(+), 3 deletions(-)

diff --git a/net/can/af_can.c b/net/can/af_can.c
index 1684ba5b51eb..80d0ec599439 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -958,6 +958,8 @@ static struct pernet_operations can_pernet_ops __read_mostly = {

static __init int can_init(void)
{
+ int err;
+
/* check for correct padding to be able to use the structs similarly */
BUILD_BUG_ON(offsetof(struct can_frame, can_dlc) !=
offsetof(struct canfd_frame, len) ||
@@ -971,15 +973,31 @@ static __init int can_init(void)
if (!rcv_cache)
return -ENOMEM;

- register_pernet_subsys(&can_pernet_ops);
+ err = register_pernet_subsys(&can_pernet_ops);
+ if (err)
+ goto out_pernet;

/* protocol register */
- sock_register(&can_family_ops);
- register_netdevice_notifier(&can_netdev_notifier);
+ err = sock_register(&can_family_ops);
+ if (err)
+ goto out_sock;
+ err = register_netdevice_notifier(&can_netdev_notifier);
+ if (err)
+ goto out_notifier;
+
dev_add_pack(&can_packet);
dev_add_pack(&canfd_packet);

return 0;
+
+out_notifier:
+ sock_unregister(PF_CAN);
+out_sock:
+ unregister_pernet_subsys(&can_pernet_ops);
+out_pernet:
+ kmem_cache_destroy(rcv_cache);
+
+ return err;
}

static __exit void can_exit(void)
--
2.20.1