The patch below does not apply to the 6.0-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

Possible dependencies:

0acc442309a0 ("can: af_can: fix NULL pointer dereference in can_rcv_filter") fb08cba12b52 ("can: canxl: update CAN infrastructure for CAN XL frames") 467ef4c7b9d1 ("can: skb: add skb CAN frame data length helpers") 96a7457a14d9 ("can: skb: unify skb CAN frame identification helpers")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 0acc442309a0a1b01bcdaa135e56e6398a49439c Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp socketcan@hartkopp.net Date: Tue, 6 Dec 2022 21:12:59 +0100 Subject: [PATCH] can: af_can: fix NULL pointer dereference in can_rcv_filter

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

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);