CVE-2024-43820 dm-raid: Fix WARN_ON_ONCE check for sync_thread in raid_resume
A logic error in the Linux kernel dm-raid module can trigger a kernel warning during device resume, potentially leading to system instability or denial of service.
- 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-2024-43820?
CVE-2024-43820 is a medium-severity denial of service vulnerability in Linux kernel, published on 17 Aug 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:
dm-raid: Fix WARN_ON_ONCE check for sync_thread in raid_resume
rm-raid devices will occasionally trigger the following warning when being resumed after a table load because DM_RECOVERY_RUNNING is set:
WARNING: CPU: 7 PID: 5660 at drivers/md/dm-raid.c:4105 raid_resume+0xee/0x100 [dm_raid]
The failing check is: WARN_ON_ONCE(test_bit(MD_RECOVERY_RUNNING, &mddev->recovery));
This check is designed to make sure that the sync thread isn't registered, but md_check_recovery can set MD_RECOVERY_RUNNING without the sync_thread ever getting registered. Instead of checking if MD_RECOVERY_RUNNING is set, check if sync_thread is non-NULL.
Which versions are affected by CVE-2024-43820?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-43820?
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-2024-43820 being exploited?
There is no known exploitation of CVE-2024-43820 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-43820, DEBIAN-CVE-2024-43820, GHSA-cmr7-73x3-27cg, UBUNTU-CVE-2024-43820.