CVE-2022-49863

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

can: af_can: fix NULL pointer dereference in can_rx_register()

It causes NULL pointer dereference when testing as following:

(a) use syscall(__NR_socket, 0x10ul, 3ul, 0) to create netlink socket.

(b) use syscall(__NR_sendmsg, ...) to create bond link device and vxcan

link device, and bind vxcan device to bond device (can also use

ifenslave command to bind vxcan device to bond device).

(c) use syscall(__NR_socket, 0x1dul, 3ul, 1) to create CAN socket.

(d) use syscall(__NR_bind, ...) to bind the bond device to CAN socket.

The bond device invokes the can-raw protocol registration interface to

receive CAN packets. However, ml_priv is not allocated to the dev,

dev_rcv_lists is assigned to NULL in can_rx_register(). In this case,

it will occur the NULL pointer dereference issue.

The following is the stack information:

BUG: kernel NULL pointer dereference, address: 0000000000000008

PGD 122a4067 P4D 122a4067 PUD 12

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References