CVE-2023-53678

Published Oct 7, 2025

Last updated 8 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: drm/i915: Fix system suspend without fbdev being initialized If fbdev is not initialized for some reason - in practice on platforms without display - suspending fbdev should be skipped during system suspend, fix this up. While at it add an assert that suspending fbdev only happens with the display present. This fixes the following: [ 91.227923] PM: suspend entry (s2idle) [ 91.254598] Filesystems sync: 0.025 seconds [ 91.270518] Freezing user space processes [ 91.272266] Freezing user space processes completed (elapsed 0.001 seconds) [ 91.272686] OOM killer disabled. [ 91.272872] Freezing remaining freezable tasks [ 91.274295] Freezing remaining freezable tasks completed (elapsed 0.001 seconds) [ 91.659622] BUG: kernel NULL pointer dereference, address: 00000000000001c8 [ 91.659981] #PF: supervisor write access in kernel mode [ 91.660252] #PF: error_code(0x0002) - not-present page [ 91.660511] PGD 0 P4D 0 [ 91.660647] Oops: 0002 [#1] PREEMPT SMP NOPTI [ 91.660875] CPU: 4 PID: 917 Comm: bash Not tainted 6.2.0-rc7+ #54 [ 91.661185] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS edk2-20221117gitfff6d81270b5-9.fc37 unknown [ 91.661680] RIP: 0010:mutex_lock+0x19/0x30 [ 91.661914] Code: 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 0f 1f 44 00 00 53 48 89 fb e8 62 d3 ff ff 31 c0 65 48 8b 14 25 00 15 03 00 <f0> 48 0f b1 13 75 06 5b c3 cc cc cc cc 48 89 df 5b eb b4 0f 1f 40 [ 91.662840] RSP: 0018:ffffa1e8011ffc08 EFLAGS: 00010246 [ 91.663087] RAX: 0000000000000000 RBX: 00000000000001c8 RCX: 0000000000000000 [ 91.663440] RDX: ffff8be455eb0000 RSI: 0000000000000001 RDI: 00000000000001c8 [ 91.663802] RBP: ffff8be459440000 R08: ffff8be459441f08 R09: ffffffff8e1432c0 [ 91.664167] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000001 [ 91.664532] R13: 00000000000001c8 R14: 0000000000000000 R15: ffff8be442f4fb20 [ 91.664905] FS: 00007f28ffc16740(0000) GS:ffff8be4bb900000(0000) knlGS:0000000000000000 [ 91.665334] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 91.665626] CR2: 00000000000001c8 CR3: 0000000114926006 CR4: 0000000000770ee0 [ 91.665988] PKRU: 55555554 [ 91.666131] Call Trace: [ 91.666265] <TASK> [ 91.666381] intel_fbdev_set_suspend+0x97/0x1b0 [i915] [ 91.666738] i915_drm_suspend+0xb9/0x100 [i915] [ 91.667029] pci_pm_suspend+0x78/0x170 [ 91.667234] ? __pfx_pci_pm_suspend+0x10/0x10 [ 91.667461] dpm_run_callback+0x47/0x150 [ 91.667673] __device_suspend+0x10a/0x4e0 [ 91.667880] dpm_suspend+0x134/0x270 [ 91.668069] dpm_suspend_start+0x79/0x80 [ 91.668272] suspend_devices_and_enter+0x11b/0x890 [ 91.668526] pm_suspend.cold+0x270/0x2fc [ 91.668737] state_store+0x46/0x90 [ 91.668916] kernfs_fop_write_iter+0x11b/0x200 [ 91.669153] vfs_write+0x1e1/0x3a0 [ 91.669336] ksys_write+0x53/0xd0 [ 91.669510] do_syscall_64+0x58/0xc0 [ 91.669699] ? syscall_exit_to_user_mode_prepare+0x18e/0x1c0 [ 91.669980] ? syscall_exit_to_user_mode_prepare+0x18e/0x1c0 [ 91.670278] ? syscall_exit_to_user_mode+0x17/0x40 [ 91.670524] ? do_syscall_64+0x67/0xc0 [ 91.670717] ? __irq_exit_rcu+0x3d/0x140 [ 91.670931] entry_SYSCALL_64_after_hwframe+0x72/0xdc [ 91.671202] RIP: 0033:0x7f28ffd14284 v2: CC stable. (Jani) References: https://gitlab.freedesktop.org/drm/intel/-/issues/8015 (cherry picked from commit 9542d708409a41449e99c9a464deb5e062c4bee2)
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
CWE-476

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