CVE-2022-50298

Published Sep 15, 2025

Last updated a year ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: slimbus: qcom-ngd: cleanup in probe error path Add proper error path in probe() to cleanup resources previously acquired/allocated to fix warnings visible during probe deferral: notifier callback qcom_slim_ngd_ssr_notify already registered WARNING: CPU: 6 PID: 70 at kernel/notifier.c:28 notifier_chain_register+0x5c/0x90 Modules linked in: CPU: 6 PID: 70 Comm: kworker/u16:1 Not tainted 6.0.0-rc3-next-20220830 #380 Call trace: notifier_chain_register+0x5c/0x90 srcu_notifier_chain_register+0x44/0x90 qcom_register_ssr_notifier+0x38/0x4c qcom_slim_ngd_ctrl_probe+0xd8/0x400 platform_probe+0x6c/0xe0 really_probe+0xbc/0x2d4 __driver_probe_device+0x78/0xe0 driver_probe_device+0x3c/0x12c __device_attach_driver+0xb8/0x120 bus_for_each_drv+0x78/0xd0 __device_attach+0xa8/0x1c0 device_initial_probe+0x18/0x24 bus_probe_device+0xa0/0xac deferred_probe_work_func+0x88/0xc0 process_one_work+0x1d4/0x320 worker_thread+0x2cc/0x44c kthread+0x110/0x114 ret_from_fork+0x10/0x20
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
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