CVE-2025-23149

Published May 1, 2025

Last updated a year ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: tpm: do not start chip while suspended Checking TPM_CHIP_FLAG_SUSPENDED after the call to tpm_find_get_ops() can lead to a spurious tpm_chip_start() call: [35985.503771] i2c i2c-1: Transfer while suspended [35985.503796] WARNING: CPU: 0 PID: 74 at drivers/i2c/i2c-core.h:56 __i2c_transfer+0xbe/0x810 [35985.503802] Modules linked in: [35985.503808] CPU: 0 UID: 0 PID: 74 Comm: hwrng Tainted: G W 6.13.0-next-20250203-00005-gfa0cb5642941 #19 9c3d7f78192f2d38e32010ac9c90fdc71109ef6f [35985.503814] Tainted: [W]=WARN [35985.503817] Hardware name: Google Morphius/Morphius, BIOS Google_Morphius.13434.858.0 10/26/2023 [35985.503819] RIP: 0010:__i2c_transfer+0xbe/0x810 [35985.503825] Code: 30 01 00 00 4c 89 f7 e8 40 fe d8 ff 48 8b 93 80 01 00 00 48 85 d2 75 03 49 8b 16 48 c7 c7 0a fb 7c a7 48 89 c6 e8 32 ad b0 fe <0f> 0b b8 94 ff ff ff e9 33 04 00 00 be 02 00 00 00 83 fd 02 0f 5 [35985.503828] RSP: 0018:ffffa106c0333d30 EFLAGS: 00010246 [35985.503833] RAX: 074ba64aa20f7000 RBX: ffff8aa4c1167120 RCX: 0000000000000000 [35985.503836] RDX: 0000000000000000 RSI: ffffffffa77ab0e4 RDI: 0000000000000001 [35985.503838] RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000 [35985.503841] R10: 0000000000000004 R11: 00000001000313d5 R12: ffff8aa4c10f1820 [35985.503843] R13: ffff8aa4c0e243c0 R14: ffff8aa4c1167250 R15: ffff8aa4c1167120 [35985.503846] FS: 0000000000000000(0000) GS:ffff8aa4eae00000(0000) knlGS:0000000000000000 [35985.503849] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [35985.503852] CR2: 00007fab0aaf1000 CR3: 0000000105328000 CR4: 00000000003506f0 [35985.503855] Call Trace: [35985.503859] <TASK> [35985.503863] ? __warn+0xd4/0x260 [35985.503868] ? __i2c_transfer+0xbe/0x810 [35985.503874] ? report_bug+0xf3/0x210 [35985.503882] ? handle_bug+0x63/0xb0 [35985.503887] ? exc_invalid_op+0x16/0x50 [35985.503892] ? asm_exc_invalid_op+0x16/0x20 [35985.503904] ? __i2c_transfer+0xbe/0x810 [35985.503913] tpm_cr50_i2c_transfer_message+0x24/0xf0 [35985.503920] tpm_cr50_i2c_read+0x8e/0x120 [35985.503928] tpm_cr50_request_locality+0x75/0x170 [35985.503935] tpm_chip_start+0x116/0x160 [35985.503942] tpm_try_get_ops+0x57/0x90 [35985.503948] tpm_find_get_ops+0x26/0xd0 [35985.503955] tpm_get_random+0x2d/0x80 Don't move forward with tpm_chip_start() inside tpm_try_get_ops(), unless TPM_CHIP_FLAG_SUSPENDED is not set. tpm_find_get_ops() will return NULL in such a failure case.
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