Cloudanix VulnDB

CVE-2026-99089

None

CVSS

—

EPSS

0.2%

Published

Oct 26, 2026

CISA due date

—

Cloudanix analysis

Schedule a fix SSVC: Track

A clock management mistake in an audio driver for certain devices can produce warning messages when the system starts or suspends power.

Exploitation
Other
Attacker needs
None
Complexity
Theoretical
Impact
Denial Of Service
Component
OS kernel
Class
Other
Remediation
Patch
Effort
Low
Patch risk
Low

What it actually does

Clock enable/disable imbalance in the Samsung I2S audio driver where op_clk is acquired but not enabled during probe, causing the runtime PM suspend path to issue an extra disable and trigger a kernel warning on clk_core_disable.

Why it matters to the business

Boot-time kernel warnings and potential audio subsystem instability on affected Exynos-based devices; low operational impact but indicates misconfigured power management that may affect reliability in embedded or mobile deployments.

How an attack unfolds

No attacker exploitation path exists; the flaw is triggered automatically during normal device probe and subsequent runtime PM suspend on hardware where both clocks resolve to the same gate, such as Exynos5250 Arndale boards.

How to fix it

Update to a kernel containing the fix that enables op_clk immediately after acquiring it in probe and disables it in remove; rebuild and deploy the updated snd_soc_i2s driver module.

How to confirm the fix worked

Confirm absence of the clk_core_disable warning referencing i2s_bus during boot and runtime PM transitions after applying the updated driver; inspect probe and remove functions for balanced op_clk enable/disable calls.

Typical attack path

  1. Load the snd_soc_i2s module triggering probe
  2. Runtime PM active state entered with only iis clock enabled
  3. First runtime suspend calls i2s_runtime_suspend which disables op_clk without matching prior enable
  4. Kernel emits WARNING at clk_core_disable for already-disabled clock

How to detect it

Search kernel logs for the exact warning string from clk_core_disable mentioning i2s_bus already disabled and the call trace through i2s_runtime_suspend and pm_runtime_work.

What your security team should do

  • Apply the upstream fix in the next kernel update cycle for affected Samsung/Exynos platforms
  • Monitor kernel logs for clk warnings on boot of audio-enabled devices
  • Prioritize testing on Exynos5250 and similar boards where clocks share a gate

The record

In the Linux kernel, the following vulnerability has been resolved: ASoC: samsung: i2s: enable op_clk in probe to balance runtime PM The probe function puts the device into the runtime PM active state with only the "iis" bus clock enabled, but it also sets priv->op_clk to the parent of the RCLK_SRC mux without enabling it. The runtime PM suspend callback disables both clocks, so the first runtime suspend after probe disables op_clk once more than it was enabled. On Exynos5250 Arndale both clocks resolve to the same EXYNOS_I2S_BUS gate, so this triggers the following warning during boot: WARNING: drivers/clk/clk.c:1270 at clk_core_disable+0xe4/0x23c, CPU#0: kworker/u8:3/45 i2s_bus already disabled ... Workqueue: pm pm_runtime_work Call trace: ... clk_core_disable from clk_disable+0x28/0x34 clk_disable from i2s_runtime_suspend+0x58/0x68 [snd_soc_i2s] i2s_runtime_suspend [snd_soc_i2s] from genpd_runtime_suspend+0xc4/0x298 genpd_runtime_suspend from __rpm_callback+0x48/0x18c __rpm_callback from rpm_callback+0x4c/0x50 rpm_callback from rpm_suspend+0xf4/0x718 rpm_suspend from pm_runtime_work+0x9c/0xa0 ... Fix this by enabling op_clk in probe right after getting it, so the clock state matches the runtime PM active state, and by disabling it in remove.

Affected packages

Ecosystem Package Introduced Fixed