CVE-2024-27389 pstore: inode: Only d_invalidate() is needed
A double-free bug in the Linux kernel pstore filesystem can cause a system crash when unloading a modular backend with existing records.
- 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-2024-27389?
CVE-2024-27389 is a high-severity denial of service vulnerability in Linux kernel, published on 1 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:
pstore: inode: Only d_invalidate() is needed
Unloading a modular pstore backend with records in pstorefs would trigger the dput() double-drop warning:
WARNING: CPU: 0 PID: 2569 at fs/dcache.c:762 dput.part.0+0x3f3/0x410
Using the combo of d_drop()/dput() (as mentioned in Documentation/filesystems/vfs.rst) isn't the right approach here, and leads to the reference counting problem seen above. Use d_invalidate() and update the code to not bother checking for error codes that can never happen.
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Weakness: CWE-415
Which versions are affected by CVE-2024-27389?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-27389?
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-2024-27389 being exploited?
There is no known exploitation of CVE-2024-27389 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-67496, BELL-CVE-2024-27389, DEBIAN-CVE-2024-27389, GHSA-j54f-72m2-vvmr, ROOT-OS-DEBIAN-11-CVE-2024-27389, ROOT-OS-UBUNTU-2204-CVE-2024-27389 and 1 more.