CVE-2024-46851 drm/amd/display: Avoid race between dcn10_set_drr() and dc_state_destruct()
A race condition in the Linux kernel AMD display driver can lead to a null pointer dereference and system crash.
- 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-2024-46851?
CVE-2024-46851 is a medium-severity vulnerability in Linux kernel, published on 27 Sep 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/amd/display: Avoid race between dcn10_set_drr() and dc_state_destruct()
dc_state_destruct() nulls the resource context of the DC state. The pipe context passed to dcn10_set_drr() is a member of this resource context.
If dc_state_destruct() is called parallel to the IRQ processing (which calls dcn10_set_drr() at some point), we can end up using already nulled function callback fields of struct stream_resource.
The logic in dcn10_set_drr() already tries to avoid this, by checking tg against NULL. But if the nulling happens exactly after the NULL check and before the next access, then we get a race.
Avoid this by copying tg first to a local variable, and then use this variable for all the operations. This should work, as long as nobody frees the resource pool where the timing generators live.
(cherry picked from commit a3cc326a43bdc48fbdf53443e1027a03e309b643)
Weakness: CWE-476
Which versions are affected by CVE-2024-46851?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-46851?
Apply the vendor's patch.
Is CVE-2024-46851 being exploited?
There is no known exploitation of CVE-2024-46851 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-46851, DEBIAN-CVE-2024-46851, GHSA-mjph-w86f-8cqm, UBUNTU-CVE-2024-46851.