CVE-2025-71229

Published Feb 18, 2026

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: wifi: rtw88: Fix alignment fault in rtw_core_enable_beacon() rtw_core_enable_beacon() reads 4 bytes from an address that is not a multiple of 4. This results in a crash on some systems. Do 1 byte reads/writes instead. Unable to handle kernel paging request at virtual address ffff8000827e0522 Mem abort info: ESR = 0x0000000096000021 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x21: alignment fault Data abort info: ISV = 0, ISS = 0x00000021, ISS2 = 0x00000000 CM = 0, WnR = 0, TnD = 0, TagAccess = 0 GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0 swapper pgtable: 4k pages, 48-bit VAs, pgdp=0000000005492000 [ffff8000827e0522] pgd=0000000000000000, p4d=10000001021d9403, pud=10000001021da403, pmd=100000011061c403, pte=00780000f3200f13 Internal error: Oops: 0000000096000021 [#1] SMP Modules linked in: [...] rtw88_8822ce rtw88_8822c rtw88_pci rtw88_core [...] CPU: 0 UID: 0 PID: 73 Comm: kworker/u32:2 Tainted: G W 6.17.9 #1-NixOS VOLUNTARY Tainted: [W]=WARN Hardware name: FriendlyElec NanoPC-T6 LTS (DT) Workqueue: phy0 rtw_c2h_work [rtw88_core] pstate: 60400009 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : rtw_pci_read32+0x18/0x40 [rtw88_pci] lr : rtw_core_enable_beacon+0xe0/0x148 [rtw88_core] sp : ffff800080cc3ca0 x29: ffff800080cc3ca0 x28: ffff0001031fc240 x27: ffff000102100828 x26: ffffd2cb7c9b4088 x25: ffff0001031fc2c0 x24: ffff000112fdef00 x23: ffff000112fdef18 x22: ffff000111c29970 x21: 0000000000000001 x20: 0000000000000001 x19: ffff000111c22040 x18: 0000000000000000 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : ffffd2cb6507c090 x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 x5 : 0000000000000000 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000007f10 x1 : 0000000000000522 x0 : ffff8000827e0522 Call trace: rtw_pci_read32+0x18/0x40 [rtw88_pci] (P) rtw_hw_scan_chan_switch+0x124/0x1a8 [rtw88_core] rtw_fw_c2h_cmd_handle+0x254/0x290 [rtw88_core] rtw_c2h_work+0x50/0x98 [rtw88_core] process_one_work+0x178/0x3f8 worker_thread+0x208/0x418 kthread+0x120/0x220 ret_from_fork+0x10/0x20 Code: d28fe202 8b020000 f9524400 8b214000 (b9400000) ---[ end trace 0000000000000000 ]---
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