CVE-2023-54033

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

bpf: fix a memory leak in the LRU and LRU_PERCPU hash maps

The LRU and LRU_PERCPU maps allocate a new element on update before locking the

target hash table bucket. Right after that the maps try to lock the bucket.

If this fails, then maps return -EBUSY to the caller without releasing the

allocated element. This makes the element untracked: it doesn't belong to

either of free lists, and it doesn't belong to the hash table, so can't be

re-used; this eventually leads to the permanent -ENOMEM on LRU map updates,

which is unexpected. Fix this by returning the element to the local free list

if bucket locking fails.

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References