CVE-2025-71132
Vulnerability Summary
Timeline
Description
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 Metrics
- v3.1•MEDIUM•Score: 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- v3.1•HIGH•Score: 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Trends
Current EPSS score: 0.27%• Percentile: 20%
Affected Systems
- debian•linux
< 6.1.162-1 | < 6.12.69-1 | < 6.18.5-1
- debian•linux-6.1
< 6.1.162-1~deb11u1
- ubuntu•linux
< 5.15.0-173.183 | < 6.8.0-110.110 | < 6.17.0-22.22
- ubuntu•linux-allwinner-5.19
all
- ubuntu•linux-aws
< 5.15.0-1103.110 | < 6.8.0-1052.55 | < 6.17.0-1012.12
- ubuntu•linux-aws-5.0
all
- ubuntu•linux-aws-5.11
all
- ubuntu•linux-aws-5.13
all
- ubuntu•linux-aws-5.15
< 5.15.0-1103.110~20.04.1
- ubuntu•linux-aws-5.19
all
- ubuntu•linux-aws-5.3
all
- ubuntu•linux-aws-5.8
all
- ubuntu•linux-aws-6.14
all
- ubuntu•linux-aws-6.17
< 6.17.0-1012.12~24.04.1
- ubuntu•linux-aws-6.2
all
- ubuntu•linux-aws-6.5
all
- ubuntu•linux-aws-6.8
< 6.8.0-1052.55~22.04.1
- ubuntu•linux-aws-fips
all | < 5.15.0-1103.110+fips1 | < 6.8.0-1052.55+fips1
- ubuntu•linux-azure
all | < 5.15.0-1109.118 | < 6.8.0-1054.60 | < 6.17.0-1013.13
- ubuntu•linux-azure-5.11
all
- ubuntu•linux-azure-5.13
all
- ubuntu•linux-azure-5.15
< 5.15.0-1110.119~20.04.1
- ubuntu•linux-azure-5.19
all
- ubuntu•linux-azure-5.3
all
- ubuntu•linux-azure-5.8
all
- ubuntu•linux-azure-6.11
all
- ubuntu•linux-azure-6.14
all
- ubuntu•linux-azure-6.17
< 6.17.0-1013.13~24.04.1
- ubuntu•linux-azure-6.2
all
- ubuntu•linux-azure-6.5
all
- ubuntu•linux-azure-6.8
< 6.8.0-1059.65~22.04.1
- ubuntu•linux-azure-edge
all
- ubuntu•linux-azure-fde
all | all | all | all
- ubuntu•linux-azure-fde-5.19
all
- ubuntu•linux-azure-fde-6.14
all
- ubuntu•linux-azure-fde-6.2
all
- ubuntu•linux-azure-fde-6.8
all
- ubuntu•linux-azure-fips
all | < 5.15.0-1109.118+fips1 | < 6.8.0-1053.59+fips1
- ubuntu•linux-azure-nvidia
all
- ubuntu•linux-azure-nvidia-6.14
all
- ubuntu•linux-bluefield
all | < 5.15.0-1086.88 | < 6.8.0-1017.21
- ubuntu•linux-fips
all | < 5.15.0-173.183+fips1 | < 6.8.0-110.110+fips2
- ubuntu•linux-gcp
all | < 5.15.0-1103.112 | < 6.8.0-1054.57 | < 6.17.0-1012.12
- ubuntu•linux-gcp-5.11
all
- ubuntu•linux-gcp-5.13
all
- ubuntu•linux-gcp-5.15
< 5.15.0-1103.112~20.04.1
- ubuntu•linux-gcp-5.19
all
- ubuntu•linux-gcp-5.3
all
- ubuntu•linux-gcp-5.8
all
- ubuntu•linux-gcp-6.11
all
Showing first 50 affected entries in server-rendered view.
References (39)
- https://git.kernel.org/stable/c/1c4cb705e733250d13243f6a69b8b5a92e39b9f6
- https://git.kernel.org/stable/c/9d222141b00156509d67d80c771fbefa92c43ace
- https://git.kernel.org/stable/c/ef277ae121b3249c99994652210a326b52d527b0
- https://git.kernel.org/stable/c/36561b86cb2501647662cfaf91286dd6973804a6
- https://git.kernel.org/stable/c/b6018d5c1a8f09d5efe4d6961d7ee45fdf3a7ce3
- https://git.kernel.org/stable/c/6402078bd9d1ed46e79465e1faaa42e3458f8a33
- https://ubuntu.com/security/CVE-2025-71132
- https://www.cve.org/CVERecord?id=CVE-2025-71132
- https://ubuntu.com/security/notices/USN-8096-1
- https://ubuntu.com/security/notices/USN-8096-2
- https://ubuntu.com/security/notices/USN-8096-3
- https://ubuntu.com/security/notices/USN-8096-4
- https://ubuntu.com/security/notices/USN-8116-1
- https://ubuntu.com/security/notices/USN-8096-5
- https://ubuntu.com/security/notices/USN-8141-1
- https://ubuntu.com/security/notices/USN-8163-1
- https://ubuntu.com/security/notices/USN-8163-2
- https://ubuntu.com/security/notices/USN-8177-1
- https://ubuntu.com/security/notices/USN-8179-1
- https://ubuntu.com/security/notices/USN-8177-2
- https://ubuntu.com/security/notices/USN-8183-1
- https://ubuntu.com/security/notices/USN-8184-1
- https://ubuntu.com/security/notices/USN-8179-2
- https://ubuntu.com/security/notices/USN-8185-1
- https://ubuntu.com/security/notices/USN-8183-2
- https://ubuntu.com/security/notices/USN-8179-3
- https://ubuntu.com/security/notices/USN-8203-1
- https://ubuntu.com/security/notices/USN-8204-1
- https://ubuntu.com/security/notices/USN-8185-2
- https://ubuntu.com/security/notices/USN-8179-4
- https://ubuntu.com/security/notices/USN-8243-1
- https://ubuntu.com/security/notices/USN-8245-1
- https://ubuntu.com/security/notices/USN-8257-1
- https://ubuntu.com/security/notices/USN-8258-1
- https://ubuntu.com/security/notices/USN-8260-1
- https://ubuntu.com/security/notices/USN-8261-1
- https://ubuntu.com/security/notices/USN-8265-1
- https://ubuntu.com/security/notices/USN-8440-1
- https://security-tracker.debian.org/tracker/CVE-2025-71132