CVE-2025-38168

Published Jul 3, 2025

Last updated 8 days ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: perf: arm-ni: Unregister PMUs on probe failure When a resource allocation fails in one clock domain of an NI device, we need to properly roll back all previously registered perf PMUs in other clock domains of the same device. Otherwise, it can lead to kernel panics. Calling arm_ni_init+0x0/0xff8 [arm_ni] @ 2374 arm-ni ARMHCB70:00: Failed to request PMU region 0x1f3c13000 arm-ni ARMHCB70:00: probe with driver arm-ni failed with error -16 list_add corruption: next->prev should be prev (fffffd01e9698a18), but was 0000000000000000. (next=ffff10001a0decc8). pstate: 6340009 (nZCv daif +PAN -UAO +TCO +DIT -SSBS BTYPE=--) pc : list_add_valid_or_report+0x7c/0xb8 lr : list_add_valid_or_report+0x7c/0xb8 Call trace: __list_add_valid_or_report+0x7c/0xb8 perf_pmu_register+0x22c/0x3a0 arm_ni_probe+0x554/0x70c [arm_ni] platform_probe+0x70/0xe8 really_probe+0xc6/0x4d8 driver_probe_device+0x48/0x170 __driver_attach+0x8e/0x1c0 bus_for_each_dev+0x64/0xf0 driver_add+0x138/0x260 bus_add_driver+0x68/0x138 __platform_driver_register+0x2c/0x40 arm_ni_init+0x14/0x2a [arm_ni] do_init_module+0x36/0x298 ---[ end trace 0000000000000000 ]--- Kernel panic - not syncing: Oops - BUG: Fatal exception SMP: stopping secondary CPUs
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: cgroup: Avoid iteration of dying tasks with zero refcount The commit 260fbcb92bbea ("cgroup: Move dying_tasks cleanup from cgroup_task_release() to cgroup_task_free()") extended the lifetime of tasks on the dying_tasks list. The iterators have provision to go through dying_tasks because of dying threadgroup leaders or explicit CSS_TASK_ITER_WITH_DEAD, however, it was expected that such tasks can obtain a new reference (that is possible before cgroup_task_release()/put_task_struct_rcu_user()). The tasks after cgroup_task_release() and before cgroup_task_free() are subject to race when they may or may not have ->usage count > 0. The race window is between css_task_iter_next() invocations when css_set_lock is released and we may arrive at a new ->task_pos. The iterator should not attempt to resurrect tasks whose ->usage count dropped to zero. (When that happens, __put_task_struct_rcu_cb() is already imminent and the returned task_struct would could be used after free.) As for the fix, we cannot simply check the signal->live count of a task on the dying list because that won't distinguish regular zombies waiting to be reaped from RCU remnant tasks that are going to be free'd. Therefore add an extra check to rule out ->usage==0 tasks from any iteration. The repeat: loop in css_task_iter_advance() doesn't consider ->usage count, so add a new loop to css_task_iter_next() to skip de-used tasks on the dying_list. Rough illustration of the possible race R (reader of cgroup.procs) T (thread) L (group leader) --------------------------------- -------------------------------- -------------------------------- L exits, signal->live > 0 cgroup_task_dead(L) css_set_skip_task_iters() // skips only cset->tasks list_add_tail(&L->cg_list, &cset->dying_tasks) css_task_iter_next() take css_set_lock css_task_iter_advance() leader && signal->live != 0 => it->task_pos = &L->cg_list release css_set_lock T exits --signal->live == 0 cgroup_task_dead(T) // css_set_lock release_task(T) cgroup_task_release(T) release_task(L) // zap_leader cgroup_task_release(L) put_task_struct_rcu_user(L) ...RCU... put_task_struct(L) L->usage = 0 /* L still on dying_tasks */ ...RCU... __put_task_struct(L) css_task_iter_next() // another iteration take css_set_lock it->task_pos = &L->cg_list get_task_struct(L) => addition on 0 drop css_set_lock cgroup_task_free(L) css_set_skip_task_iters() // dying skip comes too late free_task(L) cgroup_procs_show() task_pid_vnr(L)•CVE-2026-98163