High 7.5Published Jan 14, 2026

CVE-2025-71132smc91x: fix broken irq-context in PREEMPT_RT

Updated under an hour ago (Oct 28, 2026, 2:30 AM ET)

Does this affect you?

It affects Linux and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for Linux

Exploited in the last 30 days

In the Linux kernel, the following vulnerability has been resolved: smc91x: fix broken irq-context in PREEMPT_RT When smc91x.c is built with PREEMPT_RT, the following splat occurs in FVP_RevC: [ 13.055000] smc91x LNRO0003:00 eth0: link up, 10Mbps, half-duplex, lpa 0x0000 [ 13.062137] BUG: workqueue leaked atomic, lock or RCU: kworker/2:1[106] [ 13.062137] preempt=0x00000000 lock=0->0 RCU=0->1 workfn=mld_ifc_work [ 13.062266] C ** replaying previous printk message ** [ 13.062266] CPU: 2 UID: 0 PID: 106 Comm: kworker/2:1 Not tainted 6.18.0-dirty #179 PREEMPT_{RT,(full)} [ 13.062353] Hardware name: , BIOS [ 13.062382] Workqueue: mld mld_ifc_work [ 13.062469] Call trace: [ 13.062494] show_stack+0x24/0x40 (C) [ 13.062602] __dump_stack+0x28/0x48 [ 13.062710] dump_stack_lvl+0x7c/0xb0 [ 13.062818] dump_stack+0x18/0x34 [ 13.062926] process_scheduled_works+0x294/0x450 [ 13.063043] worker_thread+0x260/0x3d8 [ 13.063124] kthread+0x1c4/0x228 [ 13.063235] ret_from_fork+0x10/0x20 This happens because smc_special_trylock() disables IRQs even on PREEMPT_RT, but smc_special_unlock() does not restore IRQs on PREEMPT_RT. The reason is that smc_special_unlock() calls spin_unlock_irqrestore(), and rcu_read_unlock_bh() in __dev_queue_xmit() cannot invoke rcu_read_unlock() through __local_bh_enable_ip() when current->softirq_disable_cnt becomes zero. To address this issue, replace smc_special_trylock() with spin_trylock_irqsave().

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-667
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Linux
NVD analysis: Modified
Record last updated: Oct 19, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Linux Linux linux:linux (from the name)	342a93247e0837101f27bbcca26f402902df98dc builds before 1c4cb705e733250d13243f6a69b8b5a92e39b9f6; 342a93247e0837101f27bbcca26f402902df98dc builds before 9d222141b00156509d67d80c771fbefa92c43ace; from 342a93247e0837101f27bbcca26f402902df98dc before ef277ae121b3249c99994652210a326b52d527b0; from 342a93247e0837101f27bbcca26f402902df98dc before 36561b86cb2501647662cfaf91286dd6973804a6; from 342a93247e0837101f27bbcca26f402902df98dc before b6018d5c1a8f09d5efe4d6961d7ee45fdf3a7ce3; from 342a93247e0837101f27bbcca26f402902df98dc before 6402078bd9d1ed46e79465e1faaa42e3458f8a33	CNA record
linux linux_kernel linux:linux_kernel	from 5.15.1 before 5.15.198; from 5.16 before 6.1.160; from 6.2 before 6.6.120; from 6.7 before 6.12.64; from 6.13 before 6.18.4; 5.15; 6.19; 6.19; and 6 more ranges	NVD

References

References

https://git.kernel.org/stable/c/1c4cb705e733250d13243f6a69b8b5a92e39b9f6	patch
https://git.kernel.org/stable/c/9d222141b00156509d67d80c771fbefa92c43ace	patch
https://git.kernel.org/stable/c/ef277ae121b3249c99994652210a326b52d527b0	patch
https://git.kernel.org/stable/c/36561b86cb2501647662cfaf91286dd6973804a6	patch
https://git.kernel.org/stable/c/b6018d5c1a8f09d5efe4d6961d7ee45fdf3a7ce3	patch
https://git.kernel.org/stable/c/6402078bd9d1ed46e79465e1faaa42e3458f8a33	patch

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.