From: Oliver Hartkopp socketcan@hartkopp.net

Analogue to commit 8aa59e355949 ("can: af_can: fix NULL pointer dereference in can_rx_register()") we need to check for a missing initialization of ml_priv in the receive path of CAN frames.

Since commit 4e096a18867a ("net: introduce CAN specific pointer in the struct net_device") the check for dev->type to be ARPHRD_CAN is not sufficient anymore since bonding or tun netdevices claim to be CAN devices but do not initialize ml_priv accordingly.

Fixes: 4e096a18867a ("net: introduce CAN specific pointer in the struct net_device") Reported-by: syzbot+2d7f58292cb5b29eb5ad@syzkaller.appspotmail.com Reported-by: Wei Chen harperchen1110@gmail.com Signed-off-by: Oliver Hartkopp socketcan@hartkopp.net Link: https://lore.kernel.org/all/20221206201259.3028-1-socketcan@hartkopp.net Cc: stable@vger.kernel.org Signed-off-by: Marc Kleine-Budde mkl@pengutronix.de --- net/can/af_can.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/can/af_can.c b/net/can/af_can.c index 27dcdcc0b808..c69168f11e44 100644 --- a/net/can/af_can.c +++ b/net/can/af_can.c @@ -677,7 +677,7 @@ static void can_receive(struct sk_buff *skb, struct net_device *dev) static int can_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - if (unlikely(dev->type != ARPHRD_CAN || (!can_is_can_skb(skb)))) { + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_can_skb(skb))) { pr_warn_once("PF_CAN: dropped non conform CAN skbuff: dev type %d, len %d\n", dev->type, skb->len);

@@ -692,7 +692,7 @@ static int can_rcv(struct sk_buff *skb, struct net_device *dev, static int canfd_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - if (unlikely(dev->type != ARPHRD_CAN || (!can_is_canfd_skb(skb)))) { + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_canfd_skb(skb))) { pr_warn_once("PF_CAN: dropped non conform CAN FD skbuff: dev type %d, len %d\n", dev->type, skb->len);

@@ -707,7 +707,7 @@ static int canfd_rcv(struct sk_buff *skb, struct net_device *dev, static int canxl_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) { - if (unlikely(dev->type != ARPHRD_CAN || (!can_is_canxl_skb(skb)))) { + if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || !can_is_canxl_skb(skb))) { pr_warn_once("PF_CAN: dropped non conform CAN XL skbuff: dev type %d, len %d\n", dev->type, skb->len);

base-commit: 1799c1b85e292fbfad99892bbea0beee925149e8