CVE-2025-38119

Published Jul 3, 2025

Last updated 9 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: scsi: core: ufs: Fix a hang in the error handler ufshcd_err_handling_prepare() calls ufshcd_rpm_get_sync(). The latter function can only succeed if UFSHCD_EH_IN_PROGRESS is not set because resuming involves submitting a SCSI command and ufshcd_queuecommand() returns SCSI_MLQUEUE_HOST_BUSY if UFSHCD_EH_IN_PROGRESS is set. Fix this hang by setting UFSHCD_EH_IN_PROGRESS after ufshcd_rpm_get_sync() has been called instead of before. Backtrace: __switch_to+0x174/0x338 __schedule+0x600/0x9e4 schedule+0x7c/0xe8 schedule_timeout+0xa4/0x1c8 io_schedule_timeout+0x48/0x70 wait_for_common_io+0xa8/0x160 //waiting on START_STOP wait_for_completion_io_timeout+0x10/0x20 blk_execute_rq+0xe4/0x1e4 scsi_execute_cmd+0x108/0x244 ufshcd_set_dev_pwr_mode+0xe8/0x250 __ufshcd_wl_resume+0x94/0x354 ufshcd_wl_runtime_resume+0x3c/0x174 scsi_runtime_resume+0x64/0xa4 rpm_resume+0x15c/0xa1c __pm_runtime_resume+0x4c/0x90 // Runtime resume ongoing ufshcd_err_handler+0x1a0/0xd08 process_one_work+0x174/0x808 worker_thread+0x15c/0x490 kthread+0xf4/0x1ec ret_from_fork+0x10/0x20 [ bvanassche: rewrote patch description ]
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Modified
Products
linux_kernel, debian_linux

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