CVE-2022-49863 Information

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 1223c067 PMD 0 Oops: 0000 [1] PREEMPT SMP RIP: 0010:can_rx_register+0x12d/0x1e0 Call Trace: raw_enable_filters+0x8d/0x120 raw_enable_allfilters+0x3b/0x130 raw_bind+0x118/0x4f0 __sys_bind+0x163/0x1a0 __x64_sys_bind+0x1e/0x30 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Reference

https://git.kernel.org/stable/c/261178a1c2623077d62e374a75c195e6c99a6f05 https://git.kernel.org/stable/c/8aa59e355949442c408408c2d836e561794c40a1 https://git.kernel.org/stable/c/a8055677b054bc2bb78beb1080fdc2dc5158c2fe https://git.kernel.org/stable/c/afab4655750fcb3fca359bc7d7214e3d634cdf9c https://git.kernel.org/stable/c/d68fa77ee3d03bad6fe84e89759ddf7005f9e9c6