CVE-2023-53431

Published Sep 18, 2025

Last updated 3 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: scsi: ses: Handle enclosure with just a primary component gracefully This reverts commit 3fe97ff3d949 ("scsi: ses: Don't attach if enclosure has no components") and introduces proper handling of case where there are no detected secondary components, but primary component (enumerated in num_enclosures) does exist. That fix was originally proposed by Ding Hui <dinghui@sangfor.com.cn>. Completely ignoring devices that have one primary enclosure and no secondary one results in ses_intf_add() bailing completely scsi 2:0:0:254: enclosure has no enumerated components scsi 2:0:0:254: Failed to bind enclosure -12ven in valid configurations such even on valid configurations with 1 primary and 0 secondary enclosures as below: # sg_ses /dev/sg0 3PARdata SES 3321 Supported diagnostic pages: Supported Diagnostic Pages [sdp] [0x0] Configuration (SES) [cf] [0x1] Short Enclosure Status (SES) [ses] [0x8] # sg_ses -p cf /dev/sg0 3PARdata SES 3321 Configuration diagnostic page: number of secondary subenclosures: 0 generation code: 0x0 enclosure descriptor list Subenclosure identifier: 0 [primary] relative ES process id: 0, number of ES processes: 1 number of type descriptor headers: 1 enclosure logical identifier (hex): 20000002ac02068d enclosure vendor: 3PARdata product: VV rev: 3321 type descriptor header and text list Element type: Unspecified, subenclosure id: 0 number of possible elements: 1 The changelog for the original fix follows ===== We can get a crash when disconnecting the iSCSI session, the call trace like this: [ffff00002a00fb70] kfree at ffff00000830e224 [ffff00002a00fba0] ses_intf_remove at ffff000001f200e4 [ffff00002a00fbd0] device_del at ffff0000086b6a98 [ffff00002a00fc50] device_unregister at ffff0000086b6d58 [ffff00002a00fc70] __scsi_remove_device at ffff00000870608c [ffff00002a00fca0] scsi_remove_device at ffff000008706134 [ffff00002a00fcc0] __scsi_remove_target at ffff0000087062e4 [ffff00002a00fd10] scsi_remove_target at ffff0000087064c0 [ffff00002a00fd70] __iscsi_unbind_session at ffff000001c872c4 [ffff00002a00fdb0] process_one_work at ffff00000810f35c [ffff00002a00fe00] worker_thread at ffff00000810f648 [ffff00002a00fe70] kthread at ffff000008116e98 In ses_intf_add, components count could be 0, and kcalloc 0 size scomp, but not saved in edev->component[i].scratch In this situation, edev->component[0].scratch is an invalid pointer, when kfree it in ses_intf_remove_enclosure, a crash like above would happen The call trace also could be other random cases when kfree cannot catch the invalid pointer We should not use edev->component[] array when the components count is 0 We also need check index when use edev->component[] array in ses_enclosure_data_process =====
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