Commit 0acc4423 authored by Oliver Hartkopp's avatar Oliver Hartkopp Committed by Marc Kleine-Budde
Browse files

can: af_can: fix NULL pointer dereference in can_rcv_filter 



Analogue to commit 8aa59e35 ("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 4e096a18 ("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: 4e096a18 ("net: introduce CAN specific pointer in the struct net_device")
Reported-by: default avatar <syzbot+2d7f58292cb5b29eb5ad@syzkaller.appspotmail.com>
Reported-by: default avatarWei Chen <harperchen1110@gmail.com>
Signed-off-by: default avatarOliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/all/20221206201259.3028-1-socketcan@hartkopp.net


Cc: stable@vger.kernel.org
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
parent 1799c1b8

net/can/af_can.c

+3 −3
Original line number Diff line number Diff line
@@ -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);