CVE-2022-50320

Published Sep 15, 2025

Last updated a year ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: ACPI: tables: FPDT: Don't call acpi_os_map_memory() on invalid phys address On a Packard Bell Dot SC (Intel Atom N2600 model) there is a FPDT table which contains invalid physical addresses, with high bits set which fall outside the range of the CPU-s supported physical address range. Calling acpi_os_map_memory() on such an invalid phys address leads to the below WARN_ON in ioremap triggering resulting in an oops/stacktrace. Add code to verify the physical address before calling acpi_os_map_memory() to fix / avoid the oops. [ 1.226900] ioremap: invalid physical address 3001000000000000 [ 1.226949] ------------[ cut here ]------------ [ 1.226962] WARNING: CPU: 1 PID: 1 at arch/x86/mm/ioremap.c:200 __ioremap_caller.cold+0x43/0x5f [ 1.226996] Modules linked in: [ 1.227016] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 6.0.0-rc3+ #490 [ 1.227029] Hardware name: Packard Bell dot s/SJE01_CT, BIOS V1.10 07/23/2013 [ 1.227038] RIP: 0010:__ioremap_caller.cold+0x43/0x5f [ 1.227054] Code: 96 00 00 e9 f8 af 24 ff 89 c6 48 c7 c7 d8 0c 84 99 e8 6a 96 00 00 e9 76 af 24 ff 48 89 fe 48 c7 c7 a8 0c 84 99 e8 56 96 00 00 <0f> 0b e9 60 af 24 ff 48 8b 34 24 48 c7 c7 40 0d 84 99 e8 3f 96 00 [ 1.227067] RSP: 0000:ffffb18c40033d60 EFLAGS: 00010286 [ 1.227084] RAX: 0000000000000032 RBX: 3001000000000000 RCX: 0000000000000000 [ 1.227095] RDX: 0000000000000001 RSI: 00000000ffffdfff RDI: 00000000ffffffff [ 1.227105] RBP: 3001000000000000 R08: 0000000000000000 R09: ffffb18c40033c18 [ 1.227115] R10: 0000000000000003 R11: ffffffff99d62fe8 R12: 0000000000000008 [ 1.227124] R13: 0003001000000000 R14: 0000000000001000 R15: 3001000000000000 [ 1.227135] FS: 0000000000000000(0000) GS:ffff913a3c080000(0000) knlGS:0000000000000000 [ 1.227146] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 1.227156] CR2: 0000000000000000 CR3: 0000000018c26000 CR4: 00000000000006e0 [ 1.227167] Call Trace: [ 1.227176] <TASK> [ 1.227185] ? acpi_os_map_iomem+0x1c9/0x1e0 [ 1.227215] ? kmem_cache_alloc_trace+0x187/0x370 [ 1.227254] acpi_os_map_iomem+0x1c9/0x1e0 [ 1.227288] acpi_init_fpdt+0xa8/0x253 [ 1.227308] ? acpi_debugfs_init+0x1f/0x1f [ 1.227339] do_one_initcall+0x5a/0x300 [ 1.227406] ? rcu_read_lock_sched_held+0x3f/0x80 [ 1.227442] kernel_init_freeable+0x28b/0x2cc [ 1.227512] ? rest_init+0x170/0x170 [ 1.227538] kernel_init+0x16/0x140 [ 1.227552] ret_from_fork+0x1f/0x30 [ 1.227639] </TASK> [ 1.227647] irq event stamp: 186819 [ 1.227656] hardirqs last enabled at (186825): [<ffffffff98184a6e>] __up_console_sem+0x5e/0x70 [ 1.227672] hardirqs last disabled at (186830): [<ffffffff98184a53>] __up_console_sem+0x43/0x70 [ 1.227686] softirqs last enabled at (186576): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160 [ 1.227701] softirqs last disabled at (186569): [<ffffffff980fbc9d>] __irq_exit_rcu+0xed/0x160 [ 1.227715] ---[ end trace 0000000000000000 ]---
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

Weaknesses

nvd@nist.gov
CWE-787

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