{"id":"CVE-2026-98581","revision":"7b412a48f323432e865ce1ba5f68903d","records":[{"revision":"7b412a48f323432e865ce1ba5f68903d","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-98581","aliases":[],"title":"nfc: llcp: Fix list corruption / refcount desync in nfc_llcp_recv_dm()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnfc: llcp: Fix list corruption / refcount desync in nfc_llcp_recv_dm()\n\nnfc_llcp_recv_dm() handles DM(NOBOUND)/DM(REJ) for a socket that is still\nlinked on local->connecting_sockets: it looks the socket up with\nnfc_llcp_connecting_sock_get(), sets sk->sk_state = LLCP_CLOSED and\nreturns, without taking the socket lock and without unlinking the socket\nfrom the connecting_sockets list.\n\nllcp_sock_release() selects the list to unlink from by sk_state: a socket\nin LLCP_CONNECTING is unlinked from connecting_sockets, otherwise from the\nsockets list.  Because recv_dm left the socket physically on\nconnecting_sockets but in the LLCP_CLOSED state, release() takes the else\nbranch and calls nfc_llcp_sock_unlink(&local->sockets, sk).  That runs\nsk_del_node_init() while holding sockets.lock, i.e. it removes the socket\nfrom the connecting_sockets hlist under the wrong lock.  A concurrent\nconnect() linking another socket onto connecting_sockets under\nconnecting_sockets.lock then mutates the same hlist unserialized, which\ncorrupts the list and desyncs the sk_add_node()/sk_del_node_init()\nsock_hold()/__sock_put() pairing.  An unprivileged local process holding\nLLCP sockets, with the DM supplied by the remote peer over an established\nLLCP link, can drive this to leak kernel sockets without bound (the\nmis-decrement goes through the non-freeing __sock_put() path, so the\nobject is never released), leading to memory exhaustion / DoS.\n\nThis is the same class of bug that was fixed in the sibling handler\nnfc_llcp_recv_cc() by commit b493ea2765cc (\"nfc: llcp: Fix use-after-free\nrace in nfc_llcp_recv_cc()\"); recv_dm did not receive the equivalent fix.\n\nFix it the same way: take lock_sock(), re-check that the socket is still\nhashed (release() may have won the race), and for the NOBOUND/REJ case\nunlink it from connecting_sockets before moving it to LLCP_CLOSED.  The\nunlink drops the connecting_sockets membership reference via\nsk_del_node_init(), leaving the socket unhashed, so the later\nnfc_llcp_sock_unlink() in llcp_sock_release() becomes a no-op and no\ndouble put occurs.","state":0,"publishedAt":"2026-10-18T15:18:54.696+00:00","modifiedAt":"2026-10-19T09:22:07.016+00:00","affected":[{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"unaffected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/nfc/llcp_core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"dd2d24add86b3b63cd87cf2feff98ae119ba19a6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"812731dd8511f5768f4ff279b3c18d85cd21da4b\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"dba1d9c7134afcb4b1bfad8c1b1b3f0ab5189b08\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"c1e9ed52a6697354366dddf190fbacee8ed2f7c5\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"7fb2c0eeb79bfad64065f539a453138abd0edda6\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"b94cf09720543cc34256c7aa88f8059cbe7c0419\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"320a2ff49bdce3f9a437b9a9ff341ff27d3bdbf1\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        },\n                        {\n                            \"version\": \"a69f32af86e389dd232b1bb2269e202c1bfcc60f\",\n                            \"lessThan\": \"bf1460acdf8cf5a07c819f59785d40f20d113099\",\n                            \"status\": \"affected\",\n                            \"versionType\": \"git\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"Linux","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"product\": \"Linux\",\n                    \"vendor\": \"Linux\",\n                    \"defaultStatus\": \"affected\",\n                    \"repo\": \"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git\",\n                    \"programFiles\": [\n                        \"net/nfc/llcp_core.c\"\n                    ],\n                    \"versions\": [\n                        {\n                            \"version\": \"3.6\",\n                            \"status\": \"affected\"\n                        },\n                        {\n                            \"version\": \"0\",\n                            \"lessThan\": \"3.6\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.10.271\",\n                            \"lessThanOrEqual\": \"5.10.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"5.15.222\",\n                            \"lessThanOrEqual\": \"5.15.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.1.189\",\n                            \"lessThanOrEqual\": \"6.1.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.6.158\",\n                            \"lessThanOrEqual\": \"6.6.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.12.112\",\n                            \"lessThanOrEqual\": \"6.12.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"6.18.55\",\n                            \"lessThanOrEqual\": \"6.18.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.2.9\",\n                            \"lessThanOrEqual\": \"7.2.*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"semver\"\n                        },\n                        {\n                            \"version\": \"7.3\",\n                            \"lessThanOrEqual\": \"*\",\n                            \"status\": \"unaffected\",\n                            \"versionType\": \"original_commit_for_fix\"\n                        }\n                    ]\n                }"}],"metrics":[],"references":["https://git.kernel.org/stable/c/dd2d24add86b3b63cd87cf2feff98ae119ba19a6","https://git.kernel.org/stable/c/812731dd8511f5768f4ff279b3c18d85cd21da4b","https://git.kernel.org/stable/c/dba1d9c7134afcb4b1bfad8c1b1b3f0ab5189b08","https://git.kernel.org/stable/c/c1e9ed52a6697354366dddf190fbacee8ed2f7c5","https://git.kernel.org/stable/c/7fb2c0eeb79bfad64065f539a453138abd0edda6","https://git.kernel.org/stable/c/b94cf09720543cc34256c7aa88f8059cbe7c0419","https://git.kernel.org/stable/c/320a2ff49bdce3f9a437b9a9ff341ff27d3bdbf1","https://git.kernel.org/stable/c/bf1460acdf8cf5a07c819f59785d40f20d113099"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-98581","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-98581","identifiers":["CVE-2026-98581"]},"retained":false,"historicalAffected":[]}],"coverage":[]}