net/smc: release the internal TCP sock on IPPROTO_SMC socket creation failure

{
  "id": "f5174c7b28e91259120b78ddaa87fecdb5427ee3474b6a9bc9be87f184224c70",
  "url": "https://osv.dev/vulnerability/CVE-2026-90065",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "net/smc: release the internal TCP sock on IPPROTO_SMC socket creation failure",
    "summary": "In the Linux kernel, the following vulnerability has been resolved: net/smc: release the internal TCP sock on IPPROTO_SMC socket creation failure IPPROTO_SMC sockets create an internal TCP sock (\"clcsock\") from the proto->init hook. When socket creation fails after proto->init has run - e.g. a cgroup BPF program attached to BPF_CGROUP_INET_SOCK_CREATE denies the socket - sk_common_release() only invokes sk_prot->destroy if it is set, but neither smc_inet_prot nor smc_inet6_prot defines it, and smc_destruct() returns early unless sk_state is SMC_CLOSED. As a result, every failing socket(AF_INET, SOCK_STREAM, IPPROTO_SMC) call leaks one tcp_sock, so an unprivileged task able to attach a deny-all BPF_CGROUP_INET_SOCK_CREATE program to its own cgroup can grow kernel memory unboundedly. Add a .destroy hook to both protos that releases the clcsock via smc_clcsock_release(). smc_sk_init() hashes the sock into the smc hashinfo before the clcsock is created, and smc_diag dumps walk that hash dereferencing smc->clcsock without taking clcsock_release_lock, while sk_common_release() calls .destroy before .unhash. Unhash the sock before releasing the clcsock, as __smc_release() does, so a concurrent dump cannot observe the release; the second unhash in sk_common_release() is a no-op.",
    "evidence": "osv:CVE-2026-90065",
    "products": [
      {
        "name": {
          "value": "Kernel",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.12.110",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "6.18.52",
            "evidence": "/affected/1/ranges"
          },
          {
            "value": "7.2.6",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "CVE-2026-90065",
      "aliases": [
        "CVE-2026-90065"
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
              "type": "GIT",
              "events": [
                {
                  "introduced": "d25a92ccae6bed02327b63d138e12e7806830f78"
                },
                {
                  "fixed": "2f4ece7fed6d915ec64b7735962c0d84d6261032"
                },
                {
                  "fixed": "84180988a455fd8e147c6b35c8df65d8b8cc76c2"
                },
                {
                  "fixed": "94a913cd521c0f0408820bcdbd80dadf076d97b5"
                },
                {
                  "fixed": "cec261b0b4c5c0b044165303198d10ffcdf3414c"
                }
              ]
            }
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90065.json"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.11.0"
                },
                {
                  "fixed": "6.12.110"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.13.0"
                },
                {
                  "fixed": "6.18.52"
                }
              ]
            },
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "6.19.0"
                },
                {
                  "fixed": "7.2.6"
                }
              ]
            }
          ],
          "package": {
            "name": "Kernel",
            "ecosystem": "Linux"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-90065.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:24.996763905Z",
      "provider": "osv",
      "references": [
        "https://git.kernel.org/stable/c/2f4ece7fed6d915ec64b7735962c0d84d6261032",
        "https://git.kernel.org/stable/c/84180988a455fd8e147c6b35c8df65d8b8cc76c2",
        "https://git.kernel.org/stable/c/94a913cd521c0f0408820bcdbd80dadf076d97b5",
        "https://git.kernel.org/stable/c/cec261b0b4c5c0b044165303198d10ffcdf3414c",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/90xxx/CVE-2026-90065.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-90065",
        "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/2026/90xxx/CVE-2026-90065.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-90065",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 491655,
  "published_at": "2026-09-17T16:05:48.269+00:00"
}