CVE-2023-53362

Published Sep 17, 2025

Last updated 9 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: bus: fsl-mc: don't assume child devices are all fsl-mc devices Changes in VFIO caused a pseudo-device to be created as child of fsl-mc devices causing a crash [1] when trying to bind a fsl-mc device to VFIO. Fix this by checking the device type when enumerating fsl-mc child devices. [1] Modules linked in: Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP CPU: 6 PID: 1289 Comm: sh Not tainted 6.2.0-rc5-00047-g7c46948a6e9c #2 Hardware name: NXP Layerscape LX2160ARDB (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : mc_send_command+0x24/0x1f0 lr : dprc_get_obj_region+0xfc/0x1c0 sp : ffff80000a88b900 x29: ffff80000a88b900 x28: ffff48a9429e1400 x27: 00000000000002b2 x26: ffff48a9429e1718 x25: 0000000000000000 x24: 0000000000000000 x23: ffffd59331ba3918 x22: ffffd59331ba3000 x21: 0000000000000000 x20: ffff80000a88b9b8 x19: 0000000000000000 x18: 0000000000000001 x17: 7270642f636d2d6c x16: 73662e3030303030 x15: ffffffffffffffff x14: ffffd59330f1d668 x13: ffff48a8727dc389 x12: ffff48a8727dc386 x11: 0000000000000002 x10: 00008ceaf02f35d4 x9 : 0000000000000012 x8 : 0000000000000000 x7 : 0000000000000006 x6 : ffff80000a88bab0 x5 : 0000000000000000 x4 : 0000000000000000 x3 : ffff80000a88b9e8 x2 : ffff80000a88b9e8 x1 : 0000000000000000 x0 : ffff48a945142b80 Call trace: mc_send_command+0x24/0x1f0 dprc_get_obj_region+0xfc/0x1c0 fsl_mc_device_add+0x340/0x590 fsl_mc_obj_device_add+0xd0/0xf8 dprc_scan_objects+0x1c4/0x340 dprc_scan_container+0x38/0x60 vfio_fsl_mc_probe+0x9c/0xf8 fsl_mc_driver_probe+0x24/0x70 really_probe+0xbc/0x2a8 __driver_probe_device+0x78/0xe0 device_driver_attach+0x30/0x68 bind_store+0xa8/0x130 drv_attr_store+0x24/0x38 sysfs_kf_write+0x44/0x60 kernfs_fop_write_iter+0x128/0x1b8 vfs_write+0x334/0x448 ksys_write+0x68/0xf0 __arm64_sys_write+0x1c/0x28 invoke_syscall+0x44/0x108 el0_svc_common.constprop.1+0x94/0xf8 do_el0_svc+0x38/0xb0 el0_svc+0x20/0x50 el0t_64_sync_handler+0x98/0xc0 el0t_64_sync+0x174/0x178 Code: aa0103f4 a9025bf5 d5384100 b9400801 (79401260) ---[ end trace 0000000000000000 ]---
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