CVE-2023-53831

/// Technical description

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

net: read sk->sk_family once in sk_mc_loop()

syzbot is playing with IPV6_ADDRFORM quite a lot these days,

and managed to hit the WARN_ON_ONCE(1) in sk_mc_loop()

We have many more similar issues to fix.

WARNING: CPU: 1 PID: 1593 at net/core/sock.c:782 sk_mc_loop+0x165/0x260

Modules linked in:

CPU: 1 PID: 1593 Comm: kworker/1:3 Not tainted 6.1.40-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023

Workqueue: events_power_efficient gc_worker

RIP: 0010:sk_mc_loop+0x165/0x260 net/core/sock.c:782

Code: 34 1b fd 49 81 c7 18 05 00 00 4c 89 f8 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 ff e8 25 36 6d fd 4d 8b 37 eb 13 e8 db 33 1b fd <0f> 0b b3 01 eb 34 e8 d0 33 1b fd 45 31 f6 49 83 c6 38 4c 89 f0 48

RSP: 0018:ffffc90000388530 EFLAGS: 00010246

RAX: ffffffff846d9b55 RBX: 0000000000000011 RCX: ffff88814f884980

RDX: 0000000000000102 RSI: ffffffff87ae5160 RDI: 0000000000000011

RBP:

/// 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