[PATCH] can: af_can: fix NULL pointer dereference in can_rcv_filter
From: Oliver Hartkopp <socketcan@hartkopp.net>
Date: 2022-12-06 20:14:02
Also in:
linux-can
Subsystem:
can network layer, the rest · Maintainers:
Oliver Hartkopp, Marc Kleine-Budde, Linus Torvalds
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 receieve 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 <redacted>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
---
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@@ -675,11 +675,11 @@ 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); kfree_skb(skb); return NET_RX_DROP;
@@ -690,11 +690,11 @@ 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); kfree_skb(skb); return NET_RX_DROP;
@@ -705,11 +705,11 @@ 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); kfree_skb(skb); return NET_RX_DROP;
--
2.30.2