net/smc: protect link down work from execute after lgr freed
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Partial Red Hat: 2 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat.
Summary
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: ffff94352091fc80 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffb638c9c0fc38 R10: ffffb638c9c0fc30 R11: ffffffffa015eb28 R12: 0000000000000002 R13: ffffb638c9c0fe20 R14: 0000000000000001 R15: ffff942f9cd051c0 FS: 0000000000000000(0000) GS:ffff943520900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f4f25214000 CR3: 000000025fbae004 CR4: 00000000007706e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: rwsem_down_write_slowpath+0x17e/0x470 smc_link_down_work+0x3c/0x60 [smc] process_one_work+0x1ac/0x350 worker_thread+0x49/0x2f0 ? rescuer_thread+0x360/0x360 kthread+0x118/0x140 ? __kthread_bind_mask+0x60/0x60 ret_from_fork+0x1f/0x30
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Linux | Linux | 5.8 and later | 6.1.122, 6.6.68, 6.12.7, 6.13 | Patch available | CNA |
- Linux VendorLinux Affected 5.8 and later Fixed in 6.1.122, 6.6.68, 6.12.7, 6.13 Patch available CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | 5.8 to before 6.1.122; 6.2 to before 6.6.68; 6.7 to before 6.12.7 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* | 6.13 rc1 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* | 6.13 rc2 | Vulnerable | Linux |
| cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:* | 6.13 rc3 | Vulnerable | Linux |
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* Versions 5.8 to before 6.1.122; 6.2 to before 6.6.68; 6.7 to before 6.12.7 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:* Versions 6.13 rc1 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:* Versions 6.13 rc2 Vulnerable ·Linux
- cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:* Versions 6.13 rc3 Vulnerable ·Linux
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.1.122, 6.6.68, 6.12.7, 6.13
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 8 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 9 | Affected | No fix planned: Will not fix |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
Timeline
- 2026-10-02 Threatist record created from CVE-2024-56718
- 2026-10-03 Alias added: GHSA-q325-c4qh-6g3c
References
More Linux Kernel vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
- TI-2021-05514 Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACE KEVCVSS 3.1HIGH 8.3
Sources
- CVE-2024-56718 · CVE Program
- CVE-2024-56718 · NVD
- FIRST EPSS
- GHSA-q325-c4qh-6g3c · GitHub Advisory Database · CC BY 4.0
- CVE-2024-56718 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences