CVE-2024-56718

/// Technical description

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

net/smc: protect link down work from execute after lgr freed

link down work may be scheduled before lgr freed but execute

after lgr freed, which may result in crash. So it is need to

hold a reference before shedule link down work, and put the

reference after work executed or canceled.

The relevant crash call stack as follows:

list_del corruption. prev->next should be ffffb638c9c0fe20,

but was 0000000000000000

------------[ cut here ]------------

kernel BUG at lib/list_debug.c:51!

invalid opcode: 0000 [#1] SMP NOPTI

CPU: 6 PID: 978112 Comm: kworker/6:119 Kdump: loaded Tainted: G #1

Hardware name: Alibaba Cloud Alibaba Cloud ECS, BIOS 2221b89 04/01/2014

Workqueue: events smc_link_down_work [smc]

RIP: 0010:__list_del_entry_valid.cold+0x31/0x47

RSP: 0018:ffffb638c9c0fdd8 EFLAGS: 00010086

RAX: 0000000000000054 RBX: ffff942fb75e5128 RCX: 0000000000000000

RDX: ffff943520930aa0 RSI: ffff94352091fc80 RDI: ffff

/// 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