CVE-2026-31550 pmdomain: bcm: bcm2835-power: Increase ASB control timeout
Insufficient timeout in the BCM2835 power domain driver can cause system hangs or bus faults during runtime power management suspend operations.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-31550?
CVE-2026-31550 is a medium-severity denial of service vulnerability in Linux kernel, published on 24 Apr 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:
pmdomain: bcm: bcm2835-power: Increase ASB control timeout
The bcm2835_asb_control() function uses a tight polling loop to wait for the ASB bridge to acknowledge a request. During intensive workloads, this handshake intermittently fails for V3D's master ASB on BCM2711, resulting in "Failed to disable ASB master for v3d" errors during runtime PM suspend. As a consequence, the failed power-off leaves V3D in a broken state, leading to bus faults or system hangs on later accesses.
As the timeout is insufficient in some scenarios, increase the polling timeout from 1us to 5us, which is still negligible in the context of a power domain transition. Also, replace the open-coded ktime_get_ns()/ cpu_relax() polling loop with readl_poll_timeout_atomic().
Which versions are affected by CVE-2026-31550?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-31550?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-31550 being exploited?
There is no known exploitation of CVE-2026-31550 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-31550, DEBIAN-CVE-2026-31550, GHSA-jccg-jh56-vh7j, ROOT-OS-DEBIAN-11-CVE-2026-31550, ROOT-OS-DEBIAN-12-CVE-2026-31550, ROOT-OS-UBUNTU-2204-CVE-2026-31550 and 2 more.