CVE-2026-80562 gpio: ml-ioh: use raw_spinlock_t for the register lock
A locking bug in the Linux kernel gpio: ml-ioh driver causes a deadlock on PREEMPT_RT systems, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-80562?
CVE-2026-80562 is a vulnerability in Linux, published on 26 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
gpio: ml-ioh: use raw_spinlock_t for the register lock
ioh_irq_type() is registered as the irq_chip .irq_set_type callback and takes chip->spinlock with spin_lock_irqsave(). This callback is reached from __setup_irq() -> __irq_set_trigger() -> chip->irq_set_type() while the caller holds desc->lock, a raw_spinlock_t, with hardirqs disabled. That context is not sleepable, but on PREEMPT_RT a regular spinlock_t is an rtmutex-backed sleeping lock, so acquiring it there is invalid. ioh_irq_enable() and ioh_irq_disable() take the same lock from the .irq_enable/.irq_disable callbacks, which are likewise invoked with desc->lock held.
Convert the register lock to raw_spinlock_t. The same lock also serializes the GPIO direction/value callbacks and the suspend/resume register save/restore, and those critical sections only perform short sequences of MMIO register accesses (ioread32()/iowrite32()); the .irq_set_type callback additionally emits a dev_warn() on an unsupported type. None of these are sleepable operations, so keeping this register lock non-sleeping is appropriate for the irqchip callbacks and does not change the GPIO-side locking contract.
This is the same fix as commit a02b8950d619 ("gpio: pch: use raw_spinlock_t for the register lock"); this driver shares the same structure as gpio-pch.
Which versions are affected by CVE-2026-80562?
How do I fix CVE-2026-80562?
Apply the vendor's patch.
Is CVE-2026-80562 being exploited?
There is no known exploitation of CVE-2026-80562 in the wild and no public exploit code.
Sources
Also known as AZL-97731, BELL-CVE-2026-80562, DEBIAN-CVE-2026-80562, GHSA-rxfg-5fgw-mwq5, UBUNTU-CVE-2026-80562.