CVE-2024-35952 drm/ast: Fix soft lockup
A missing timeout in the AST DRM driver causes a soft lockup, allowing local attackers to hang the system.
- 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-2024-35952?
CVE-2024-35952 is a medium-severity denial of service vulnerability in Linux kernel, published on 20 May 2024. 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/ast: Fix soft lockup
There is a while-loop in ast_dp_set_on_off() that could lead to infinite-loop. This is because the register, VGACRI-Dx, checked in this API is a scratch register actually controlled by a MCU, named DPMCU, in BMC.
These scratch registers are protected by scu-lock. If suc-lock is not off, DPMCU can not update these registers and then host will have soft lockup due to never updated status.
DPMCU is used to control DP and relative registers to handshake with host's VGA driver. Even the most time-consuming task, DP's link training, is less than 100ms. 200ms should be enough.
Weakness: CWE-667
Which versions are affected by CVE-2024-35952?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-35952?
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-2024-35952 being exploited?
There is no known exploitation of CVE-2024-35952 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-35952, DEBIAN-CVE-2024-35952, GHSA-22gp-7w9x-c2xx, UBUNTU-CVE-2024-35952.