bpf: Allow LPM map access from sleepable BPF programs

{
  "id": "cef99ce76cf81137dcc2329752c1cd2449666912b9d6eb6958098932af6d976b",
  "url": "https://osv.dev/vulnerability/CVE-2026-64352",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "bpf: Allow LPM map access from sleepable BPF programs",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: bpf: Allow LPM map access from sleepable BPF programs trie_lookup_elem() annotates its rcu_dereference_check() walks with only rcu_read_lock_bh_held(). Because rcu_dereference_check(p, c) resolves to \"c || rcu_read_lock_held()\", this passes for XDP/NAPI and classic RCU readers but fails for sleepable BPF programs, which enter via __bpf_prog_enter_sleepable() and hold only rcu_read_lock_trace(). trie_update_elem() and trie_delete_elem() have the same problem in a different form: they walk the trie with plain rcu_dereference(), which asserts rcu_read_lock_held() unconditionally. Both are reachable from sleepable BPF programs via the bpf_map_update_elem / bpf_map_delete_elem helpers, and from the syscall path under classic rcu_read_lock(). In the writer paths the trie is actually protected by trie->lock (an rqspinlock taken across the walk); we never relied on the RCU read-side lock to keep nodes alive there. A sleepable LSM hook that ends up touching an LPM trie therefore triggers lockdep on debug kernels: ============================= WARNING: suspicious RCU usage 7.1.0-... Tainted: G E ----------------------------- kernel/bpf/lpm_trie.c:249 suspicious rcu_dereference_check() usage! 1 lock held by net_tests/540: #0: (rcu_tasks_trace_srcu_struct){....}-{0:0}, at: __bpf_prog_enter_sleepable+0x26/0x280 Call Trace: dump_stack_lvl lockdep_rcu_suspicious trie_lookup_elem bpf_prog_..._enforce_security_socket_connect ",
    "evidence": "osv:CVE-2026-64352",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "5.15.212",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.1.178",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.6.145",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.12.97",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.40",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.1.4",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-64352",
      "aliases": [
        "CVE-2026-64352"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "694cea395fded425008e93cd90cfdf7a451674af"
                },
                {
                  "fixed": "f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04"
                },
                {
                  "fixed": "304ca50582f0c047370f85e13caec456f78c9fcc"
                },
                {
                  "fixed": "ec662a8b2cde01e76b37ccd4b992d0342299e69c"
                },
                {
                  "fixed": "9bfdf4b81b0e56d47bc6c46c34a46638be716695"
                },
                {
                  "fixed": "57454944737f3ad9a8703aecbbb79713b513a94b"
                },
                {
                  "fixed": "bd6ad9a6b30498d845413e863fb95c6fab3babe3"
                },
                {
                  "fixed": "2f884d371fafea137afea504d49ee4a7c8d7985b"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64352.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.14.0"
                },
                {
                  "fixed": "5.15.212"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "5.16.0"
                },
                {
                  "fixed": "6.1.178"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.2.0"
                },
                {
                  "fixed": "6.6.145"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.7.0"
                },
                {
                  "fixed": "6.12.97"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.40"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.1.4"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64352.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:32.220462281Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2f884d371fafea137afea504d49ee4a7c8d7985b",
        "https://git.kernel.org/stable/c/304ca50582f0c047370f85e13caec456f78c9fcc",
        "https://git.kernel.org/stable/c/57454944737f3ad9a8703aecbbb79713b513a94b",
        "https://git.kernel.org/stable/c/9bfdf4b81b0e56d47bc6c46c34a46638be716695",
        "https://git.kernel.org/stable/c/bd6ad9a6b30498d845413e863fb95c6fab3babe3",
        "https://git.kernel.org/stable/c/ec662a8b2cde01e76b37ccd4b992d0342299e69c",
        "https://git.kernel.org/stable/c/f0967d4f1ba4323a3cb7dc8fdba74dd3a8caaf04",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64352.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-64352",
        "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
      ],
      "provider_metadata": {
        "cna_assigner": "Linux",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64352.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-64352",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 498875,
  "published_at": "2026-07-25T08:50:11.522+00:00"
}