CVE-2026-80870 drm/amdkfd: Validate CRIU-restored IDs before idr_alloc
A local attacker can trigger a kernel warning and potential system crash by providing invalid IDs during CRIU restore operations in the AMD KFD driver.
- 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-2026-80870?
CVE-2026-80870 is a denial of service vulnerability in Linux, published on 4 Sep 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:
drm/amdkfd: Validate CRIU-restored IDs before idr_alloc
The KFD CRIU restore flow restores previously saved object IDs from userspace.
For event restore:
kfd_criu_restore_event() -> create_signal_event() / create_other_event() -> allocate_event_notification_slot() -> idr_alloc(..., *restore_id, *restore_id + 1, ...)
For BO restore:
criu_restore_memory_of_gpu() -> idr_alloc(..., bo_priv->idr_handle, ...)
In both cases, the restored ID comes from userspace-provided CRIU data.
idr_alloc() expects the ID range values to fit within signed int limits. If a restored ID is larger than INT_MAX, it can trigger a WARN in the IDR layer.
A kernel WARN is undesirable because it prints a warning trace and may cause a panic or reboot on systems with panic_on_warn enabled.
Smatch reported these paths as allowing unchecked userspace values to reach idr_alloc().
Add INT_MAX validation before using restored IDs in:
- kfd_criu_restore_event() - criu_restore_memory_of_gpu()
If the restored ID is invalid, return -EINVAL.
This prevents invalid restore data from reaching the IDR layer and avoids WARN-triggering paths, while keeping valid restore behavior unchanged.
Which versions are affected by CVE-2026-80870?
How do I fix CVE-2026-80870?
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-2026-80870 being exploited?
There is no known exploitation of CVE-2026-80870 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-80870, DEBIAN-CVE-2026-80870, GHSA-3fvv-ffr9-f4xf, UBUNTU-CVE-2026-80870.