kernel: net/smc: initialize close_work early to avoid warning (CVE-2024-56641)

Overview

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

net/smc: initialize close_work early to avoid warning

We encountered a warning that close_work was canceled before initialization.

WARNING: CPU: 7 PID: 111103 at kernel/workqueue.c:3047 __flush_work+0x19e/0x1b0 Workqueue: events smc_lgr_terminate_work [smc] RIP: 0010:__flush_work+0x19e/0x1b0 Call Trace: ? __wake_up_common+0x7a/0x190 ? work_busy+0x80/0x80 __cancel_work_timer+0xe3/0x160 smc_close_cancel_work+0x1a/0x70 [smc] smc_close_active_abort+0x207/0x360 [smc] __smc_lgr_terminate.part.38+0xc8/0x180 [smc] process_one_work+0x19e/0x340 worker_thread+0x30/0x370 ? process_one_work+0x340/0x340 kthread+0x117/0x130 ? __kthread_cancel_work+0x50/0x50 ret_from_fork+0x22/0x30

This is because when smc_close_cancel_work is triggered, e.g. the RDMA driver is rmmod and the LGR is terminated, the conn->close_work is flushed before initialization, resulting in WARN_ON(!work->func).

_smc_lgr_terminate | smc_connect{rdma|ism}

                            | smc_conn_create
			| \- smc_lgr_register_conn

for conn in lgr->conns_all | - smc_conn_kill | - smc_close_active_abort | - smc_close_cancel_work | - cancel_work_sync | - __flush_work | (close_work) | | smc_close_init | - INIT_WORK(&close_work)

So fix this by initializing close_work before establishing the connection.

Vendor advisories

• Red Hat VEX · Low · affected: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · updated 2026-10-16 · vex

kernel: net/smc: initialize close_work early to avoid warning — rated Low by Red Hat. Released 2024-12-27, updated 2026-10-16.

Affected:

• Red Hat Enterprise Linux 8
• Red Hat Enterprise Linux 9

No fix planned:

• Red Hat Enterprise Linux 8
• Red Hat Enterprise Linux 9

Not affected:

• Red Hat Enterprise Linux 6
• Red Hat Enterprise Linux 7

Remediation

Out of support scope

Workarounds / mitigations:

• Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.