{"id":"CVE-2026-93231","published":"2026-09-24T16:17:18.637","lastModified":"2026-09-24T16:17:18.637","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nlockd: fix swapped arguments in nlmsvc_match_ip()\n\nWhen releasing locks by server IP address via /proc/fs/nfsd/unlock_ip,\nnlmsvc_unlock_all_by_ip() calls nlm_traverse_files() with the server\nsockaddr as the opaque @data argument:\n\n\tnlm_traverse_files(server_addr, nlmsvc_match_ip, NULL);\n\nThe match callback is later invoked from nlm_traverse_locks() as:\n\n\tmatch(lockhost, host);\n\nwhere the first argument is the nlm_host that owns the lock, and the\nsecond argument is the @data that was originally passed down (here the\nserver sockaddr).  This is the convention every other match callback\nrelies on (nlmsvc_mark_host(), nlmsvc_same_host(), nlmsvc_is_client()):\narg1 is the real nlm_host, arg2 is the caller-supplied reference value.\n\nnlmsvc_match_ip() has had these two arguments reversed ever since the\nunlock-by-IP feature was introduced in commit 4373ea84c84d (\"lockd:\nunlock lockd locks associated with a given server ip\"):\n\n\treturn rpc_cmp_addr(nlm_srcaddr(host), datap);\n\nHere @host is actually the server sockaddr, so nlm_srcaddr(host)\ndereferences a struct sockaddr as a struct nlm_host and reads garbage\nat the offset of h_srcaddr; meanwhile @datap is actually the lock\nowner's nlm_host but is compared as a sockaddr.  As a result the\ncomparison practically never matches and locks are not released for the\nrequested IP.\n\nSwap the arguments so the lock owner's source address is compared\nagainst the requested server address:\n\n\treturn rpc_cmp_addr(nlm_srcaddr(datap), (struct sockaddr *)host);\n\n[ cel: fix the misleading typedef parameter names too ]","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/0d72e78c9d38d5377a059a4837f82b65b91cdcf6","tags":[]},{"url":"https://git.kernel.org/stable/c/21bcb609e0ab1dd60f39ca3498f85808933bcc9f","tags":[]},{"url":"https://git.kernel.org/stable/c/b9060689f49dc663e9a3d069c4a65ff63a836e66","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}