CVE-2026-43415

Published May 8, 2026

Last updated 5 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: scsi: ufs: core: Fix SError in ufshcd_rtc_work() during UFS suspend In __ufshcd_wl_suspend(), cancel_delayed_work_sync() is called to cancel the UFS RTC work, but it is placed after ufshcd_vops_suspend(hba, pm_op, POST_CHANGE). This creates a race condition where ufshcd_rtc_work() can still be running while ufshcd_vops_suspend() is executing. When UFSHCD_CAP_CLK_GATING is not supported, the condition !hba->clk_gating.active_reqs is always true, causing ufshcd_update_rtc() to be executed. Since ufshcd_vops_suspend() typically performs clock gating operations, executing ufshcd_update_rtc() at that moment triggers an SError. The kernel panic trace is as follows: Kernel panic - not syncing: Asynchronous SError Interrupt Call trace: dump_backtrace+0xec/0x128 show_stack+0x18/0x28 dump_stack_lvl+0x40/0xa0 dump_stack+0x18/0x24 panic+0x148/0x374 nmi_panic+0x3c/0x8c arm64_serror_panic+0x64/0x8c do_serror+0xc4/0xc8 el1h_64_error_handler+0x34/0x4c el1h_64_error+0x68/0x6c el1_interrupt+0x20/0x58 el1h_64_irq_handler+0x18/0x24 el1h_64_irq+0x68/0x6c ktime_get+0xc4/0x12c ufshcd_mcq_sq_stop+0x4c/0xec ufshcd_mcq_sq_cleanup+0x64/0x1dc ufshcd_clear_cmd+0x38/0x134 ufshcd_issue_dev_cmd+0x298/0x4d0 ufshcd_exec_dev_cmd+0x1a4/0x1c4 ufshcd_query_attr+0xbc/0x19c ufshcd_rtc_work+0x10c/0x1c8 process_scheduled_works+0x1c4/0x45c worker_thread+0x32c/0x3e8 kthread+0x120/0x1d8 ret_from_fork+0x10/0x20 Fix this by moving cancel_delayed_work_sync() before the call to ufshcd_vops_suspend(hba, pm_op, PRE_CHANGE), ensuring the UFS RTC work is fully completed or cancelled at that point.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
4.7
Impact score
3.6
Exploitability score
1
Vector string
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-362

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