CVE-2025-38397

Medium

In the Linux kernel, the following vulnerability has been resolved: nvme-multipath: fix suspicious RCU usage warning When I run the NVME over TCP test in virtme-ng, I get the following "suspicious RCU usage" warning in nvme_mpath_add_sysfs_link(): ''' [ 5.024557][ T44] nvmet: Created nvm controller 1 for subsystem nqn.2025-06.org.nvmexpress.mptcp for NQN nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77. [ 5.027401][ T183] nvme nvme0: creating 2 I/O queues. [ 5.029017][ T183] nvme nvme0: mapped 2/0/0 default/read/poll queues. [ 5.032587][ T183] nvme nvme0: new ctrl: NQN "nqn.2025-06.org.nvmexpress.mptcp", addr 127.0.0.1:4420, hostnqn: nqn.2014-08.org.nvmexpress:uuid:f7f6b5e0-ff97-4894-98ac-c85309e0bc77 [ 5.042214][ T25] [ 5.042440][ T25] ============================= [ 5.042579][ T25] WARNING: suspicious RCU usage [ 5.042705][ T25] 6.16.0-rc3+ #23 Not tainted [ 5.042812][ T25] ----------------------------- [ 5.042934][ T25] drivers/nvme/host/multipath.c:1203 RCU-list traversed in non-reader section!! [ 5.043111][ T25] [ 5.043111][ T25] other info that might help us debug this: [ 5.043111][ T25] [ 5.043341][ T25] [ 5.043341][ T25] rcu_scheduler_active = 2, debug_locks = 1 [ 5.043502][ T25] 3 locks held by kworker/u9:0/25: [ 5.043615][ T25] #0: ffff888008730948 ((wq_completion)async){+.+.}-{0:0}, at: process_one_work+0x7ed/0x1350 [ 5.043830][ T25] #1: ffffc900001afd40 ((work_completion)(&entry->work)){+.+.}-{0:0}, at: process_one_work+0xcf3/0x1350 [ 5.044084][ T25] #2: ffff888013ee0020 (&head->srcu){.+.+}-{0:0}, at: nvme_mpath_add_sysfs_link.part.0+0xb4/0x3a0 [ 5.044300][ T25] [ 5.044300][ T25] stack backtrace: [ 5.044439][ T25] CPU: 0 UID: 0 PID: 25 Comm: kworker/u9:0 Not tainted 6.16.0-rc3+ #23 PREEMPT(full) [ 5.044441][ T25] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 [ 5.044442][ T25] Workqueue: async async_run_entry_fn [ 5.044445][ T25] Call Trace: [ 5.044446][ T25] <TASK> [ 5.044449][ T25] dump_stack_lvl+0x6f/0xb0 [ 5.044453][ T25] lockdep_rcu_suspicious.cold+0x4f/0xb1 [ 5.044457][ T25] nvme_mpath_add_sysfs_link.part.0+0x2fb/0x3a0 [ 5.044459][ T25] ? queue_work_on+0x90/0xf0 [ 5.044461][ T25] ? lockdep_hardirqs_on+0x78/0x110 [ 5.044466][ T25] nvme_mpath_set_live+0x1e9/0x4f0 [ 5.044470][ T25] nvme_mpath_add_disk+0x240/0x2f0 [ 5.044472][ T25] ? __pfx_nvme_mpath_add_disk+0x10/0x10 [ 5.044475][ T25] ? add_disk_fwnode+0x361/0x580 [ 5.044480][ T25] nvme_alloc_ns+0x81c/0x17c0 [ 5.044483][ T25] ? kasan_quarantine_put+0x104/0x240 [ 5.044487][ T25] ? __pfx_nvme_alloc_ns+0x10/0x10 [ 5.044495][ T25] ? __pfx_nvme_find_get_ns+0x10/0x10 [ 5.044496][ T25] ? rcu_read_lock_any_held+0x45/0xa0 [ 5.044498][ T25] ? validate_chain+0x232/0x4f0 [ 5.044503][ T25] nvme_scan_ns+0x4c8/0x810 [ 5.044506][ T25] ? __pfx_nvme_scan_ns+0x10/0x10 [ 5.044508][ T25] ? find_held_lock+0x2b/0x80 [ 5.044512][ T25] ? ktime_get+0x16d/0x220 [ 5.044517][ T25] ? kvm_clock_get_cycles+0x18/0x30 [ 5.044520][ T25] ? __pfx_nvme_scan_ns_async+0x10/0x10 [ 5.044522][ T25] async_run_entry_fn+0x97/0x560 [ 5.044523][ T25] ? rcu_is_watching+0x12/0xc0 [ 5.044526][ T25] process_one_work+0xd3c/0x1350 [ 5.044532][ T25] ? __pfx_process_one_work+0x10/0x10 [ 5.044536][ T25] ? assign_work+0x16c/0x240 [ 5.044539][ T25] worker_thread+0x4da/0xd50 [ 5.044545][ T25] ? __pfx_worker_thread+0x10/0x10 [ 5.044546][ T25] kthread+0x356/0x5c0 [ 5.044548][ T25] ? __pfx_kthread+0x10/0x10 [ 5.044549][ T25] ? ret_from_fork+0x1b/0x2e0 [ 5.044552][ T25] ? __lock_release.isra.0+0x5d/0x180 [ 5.044553][ T25] ? ret_from_fork+0x1b/0x2e0 [ 5.044555][ T25] ? rcu_is_watching+0x12/0xc0 [ 5.044557][ T25] ? __pfx_kthread+0x10/0x10 [ 5.04 ---truncated---

Package Linux Kernel
Published 2025-07-25
Last modified 2025-11-19
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected versions

Linux kernel versions 6.15 and later are affected. Fixed in 6.15.6, 6.16 and their respective stable series.

Affected from
≥ 6.15
Fixed in
✓ 6.15.6 6.15.x ✓ 6.16

References

The following references provide additional information about CVE-2025-38397 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2025-38397?

    CVE-2025-38397 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 6.15 onward and has been patched in 6.15.6 and 6.16. CVE-2025-38397 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2025-38397?

    CVE-2025-38397 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2025-38397?

    Yes — CVE-2025-38397 has been patched. Fixed versions include 6.15.6 and 6.16. If you are running Linux kernel 6.15 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2025-38397 actively exploited?

    No — CVE-2025-38397 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.