CVE-2026-93231

/// Technical description

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

lockd: fix swapped arguments in nlmsvc_match_ip()

When releasing locks by server IP address via /proc/fs/nfsd/unlock_ip,

nlmsvc_unlock_all_by_ip() calls nlm_traverse_files() with the server

sockaddr as the opaque @data argument:

nlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);

The match callback is later invoked from nlm_traverse_locks() as:

match(lockhost, host);

where the first argument is the nlm_host that owns the lock, and the

second argument is the @data that was originally passed down (here the

server sockaddr). This is the convention every other match callback

relies on (nlmsvc_mark_host(), nlmsvc_same_host(), nlmsvc_is_client()):

arg1 is the real nlm_host, arg2 is the caller-supplied reference value.

nlmsvc_match_ip() has had these two arguments reversed ever since the

unlock-by-IP feature was introduced in commit 4373ea84c84d ("lockd:

unlock lockd locks associated with a given server ip"):

/// 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