CVE-2022-49914 btrfs: fix inode list leak during backref walking at resolve_indirect_refs()
A memory leak in the Linux kernel's btrfs filesystem can lead to resource exhaustion and denial of service during backref walking errors.
- 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-2022-49914?
CVE-2022-49914 is a medium-severity memory corruption vulnerability in Linux kernel, published on 1 May 2025. 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:
btrfs: fix inode list leak during backref walking at resolve_indirect_refs()
During backref walking, at resolve_indirect_refs(), if we get an error we jump to the 'out' label and call ulist_free() on the 'parents' ulist, which frees all the elements in the ulist - however that does not free any inode lists that may be attached to elements, through the 'aux' field of a ulist node, so we end up leaking lists if we have any attached to the unodes.
Fix this by calling free_leaf_list() instead of ulist_free() when we exit from resolve_indirect_refs(). The static function free_leaf_list() is moved up for this to be possible and it's slightly simplified by removing unnecessary code.
Weakness: CWE-401
Which versions are affected by CVE-2022-49914?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49914?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2022-49914 being exploited?
There is no known exploitation of CVE-2022-49914 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49914, GHSA-jgm3-v9g7-rfc3, UBUNTU-CVE-2022-49914.