Linux KernelOperating system · Linux

CVE-2025-21803

MEDIUM · 5.5 CVSS v3.1 Published 2025-02-27
Fix available
A fix is available. Upgrade to 6.6.76 / 6.12.13 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: LoongArch: Fix warnings during S3 suspend The enable_gpe_wakeup() function calls acpi_enable_all_wakeup_gpes(), and the later one may call the preempt_schedule_common() function, resulting in a thread switch and causing the CPU to be in an interrupt enabled state after the enable_gpe_wakeup() function returns, leading to the warnings as follow. [ C0] WARNING: ... at kernel/time/timekeeping.c:845 ktime_get+0xbc/0xc8 [ C0] ... [ C0] Call Trace: [ C0] [<90000000002243b4>] show_stack+0x64/0x188 [ C0] [<900000000164673c>] dump_stack_lvl+0x60/0x88 [ C0] [<90000000002687e4>] __warn+0x8c/0x148 [ C0] [<90000000015e9978>] report_bug+0x1c0/0x2b0 [ C0] [<90000000016478e4>] do_bp+0x204/0x3b8 [ C0] [<90000000025b1924>] exception_handlers+0x1924/0x10000 [ C0] [<9000000000343bbc>] ktime_get+0xbc/0xc8 [ C0] [<9000000000354c08>] tick_sched_timer+0x30/0xb0 [ C0] [<90000000003408e0>] __hrtimer_run_queues+0x160/0x378 [ C0] [<9000000000341f14>] hrtimer_interrupt+0x144/0x388 [ C0] [<9000000000228348>] constant_timer_interrupt+0x38/0x48 [ C0] [<90000000002feba4>] __handle_irq_event_percpu+0x64/0x1e8 [ C0] [<90000000002fed48>] handle_irq_event_percpu+0x20/0x80 [ C0] [<9000000000306b9c>] handle_percpu_irq+0x5c/0x98 [ C0] [<90000000002fd4a0>] generic_handle_domain_irq+0x30/0x48 [ C0] [<9000000000d0c7b0>] handle_cpu_irq+0x70/0xa8 [ C0] [<9000000001646b30>] handle_loongarch_irq+0x30/0x48 [ C0] [<9000000001646bc8>] do_vint+0x80/0xe0 [ C0] [<90000000002aea1c>] finish_task_switch.isra.0+0x8c/0x2a8 [ C0] [<900000000164e34c>] __schedule+0x314/0xa48 [ C0] [<900000000164ead8>] schedule+0x58/0xf0 [ C0] [<9000000000294a2c>] worker_thread+0x224/0x498 [ C0] [<900000000029d2f0>] kthread+0xf8/0x108 [ C0] [<9000000000221f28>] ret_from_kernel_thread+0xc/0xa4 [ C0] [ C0] ---[ end trace 0000000000000000 ]--- The root cause is acpi_enable_all_wakeup_gpes() uses a mutex to protect acpi_hw_enable_all_wakeup_gpes(), and acpi_ut_acquire_mutex() may cause a thread switch. Since there is no longer concurrent execution during loongarch_acpi_suspend(), we can call acpi_hw_enable_all_wakeup_gpes() directly in enable_gpe_wakeup(). The solution is similar to commit 22db06337f590d01 ("ACPI: sleep: Avoid breaking S3 wakeup due to might_sleep()").

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 6.2, < 6.6.76>= 6.7, < 6.12.13>= 6.13, < 6.13.2

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 6.6.76 / 6.12.13 / 6.13.2 or later
Fixed in 6.6.766.12.136.13.2
Vendor patch git.kernel.org →
Recommended fix High confidence

Linux Kernel 6.6.76, 6.12.13, or 6.13.2 (or later stable release)

  1. Identify the current kernel version using `uname -r`
  2. If running a distribution kernel (e.g., Debian, Ubuntu, RHEL), check if the vendor has released a kernel update that includes this fix
  3. If running an upstream kernel, upgrade to one of the fixed releases: 6.6.76, 6.12.13, or 6.13.2 or later
  4. Verify the fix is included by checking the kernel release notes or by reviewing the commit 194d26a5a43c in the kernel source
  5. Reboot into the updated kernel
Caveat Minor: This is a low-risk fix for LoongArch systems to correct warnings during S3 suspend. It does not introduce breaking changes but applies only to LoongArch architecture.

Generated from the published advisory — verify against the referenced sources before acting.

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-21803 in production — separate from our analysis above.

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