CVE-2024-53234 erofs: handle NONHEAD !delta[1] lclusters gracefully
A crafted EROFS filesystem image can trigger a kernel warning and impact FIEMAP operations, potentially causing 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-2024-53234?
CVE-2024-53234 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Dec 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:
erofs: handle NONHEAD !delta[1] lclusters gracefully
syzbot reported a WARNING in iomap_iter_done: iomap_fiemap+0x73b/0x9b0 fs/iomap/fiemap.c:80 ioctl_fiemap fs/ioctl.c:220 [inline]
Generally, NONHEAD lclusters won't have delta[1]==0, except for crafted images and filesystems created by pre-1.0 mkfs versions.
Previously, it would immediately bail out if delta[1]==0, which led to inadequate decompressed lengths (thus FIEMAP is impacted). Treat it as delta[1]=1 to work around these legacy mkfs versions.
`lclusterbits > 14` is illegal for compact indexes, error out too.
Which versions are affected by CVE-2024-53234?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-53234?
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-2024-53234 being exploited?
There is no known exploitation of CVE-2024-53234 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-68312, BELL-CVE-2024-53234, DEBIAN-CVE-2024-53234, GHSA-hf8q-334g-vr2p, ROOT-OS-DEBIAN-11-CVE-2024-53234, ROOT-OS-UBUNTU-2204-CVE-2024-53234 and 1 more.